You could suspect it is implantation bleeding if it occurs a bit earlier than expected, if it were scanty, spotty, pinkish and not red and heavy like a period. If your bleeding does not follow the normal pattern of a period it is probably implantation bleeding and not period.
How does implantation bleeding look like?
There is often the feeling that it is a period with light cramps and bloating, but the bleeding is shorter, lighter and simply not normal. If a woman is usually regular, and now all of a sudden develops this type of early spotting, and of course is at risk for a pregnancy, conception is recommended. Each woman should understand that implantation bleeding occurs during implantation of the egg cell. It occurs towards the end of the implantation process.
Trophoblast is a highly specialized tissue, which develops from the fertilized egg and surrounds the egg. It attaches the egg to the endometrium and, as it is continuously growing, it invades the endometrium, so as it eats its way into the endometrium it pulls the egg into the endometrium. The trophoblast also invades the mother's blood vessels and divert her blood to cavities inside the trophoblast.
These cavities are then filled by maternal blood becoming blood lakes, and most of these lakes are connected. The trophoblast on the outer surface of the egg are thinner and slower growing but also contains cavities that are connected to other deeper cavities. Some of these outer cavities communicate or open into the uterine cavity.
Blood that leaks from these cavities are causing implantation bleeding, and it occurs shortly before the egg is completely implanted and completely covered with endometrium.
Typical implantation bleeding occurs about four weeks after the last menstrual period, it is usually less and darker than the person’s normal menstruation. The diagnosis of typical implantation bleeding is made in retrospect and duration of the pregnancy is four weeks more than expected, because commonly, the last period recorded by the patient was the implantation bleeding and not her last menstruation.
Implantation bleeding has no adverse effects on a pregnancy, although some experts doubt the existence of implantation bleeding. If you search for implantation bleeding you will come across sites that doubt if it ever occurs, but the fact is that some women, about 1%-2%, has a bleeding about four weeks after the last menstrual period with a pregnancy duration four weeks longer than expected.
When does implantation bleeding usually occur?
It can happen at the time the fertilized egg implants in the uterus, on average between six to twelve days past ovulation (average 9.1 days). Unless accompanied by cramping, backache or increased bleeding, a small amount of blood being discharged should be considered as implantation bleeding, which is nothing to be concerned about. 
Home pregnancy tests
Home pregnancy test detects hormone Human Chorionic Gonadotropin or hCG in a woman’s urine. This hormone is a hormone secreted by the developing placenta shortly after a fertilized egg has been implanted in the uterine lining, so if a woman is pregnant, the amount of Human Chorionic Gonadotropin in her system should be around 25 mIU at 10 dpo. (Dpo means days past ovulation.)
It is also 50 mIU at 12 dpo, and 100 mIU at around two weeks dpo. Because of their high sensitivity factor in detecting human hCG, pregnancy tests can confirm pregnancy as early as 6-8 days past ovulation. To help lower the chances of a false negative, the best time to test at at least 9-10 days past ovulation would be advisable.
What else can cause spotting?
Because of an increase in the blood supply to your cervix and greater blood flow to the area, you might spot after having a Pap smear. You can commonly bleed after an internal exam or sex.
You may have very scant implantation bleeding, possibly around 11 or 12 days after fertilization. It is close to the time you might notice a missed period.
It may be caused by the fertilized egg burrowing into the wall of your uterus, a process that starts just six days after fertilization, but no one knows for sure. The bleeding is very light, lasting only a day or two, and only a minority of pregnant women have this kind of spotting.
Miscarriage or ectopic pregnancy could also cause spotting. Spotting can be an early sign of miscarriage or an ectopic pregnancy, especially if accompanied by abdominal pain or cramping. About a quarter of pregnant women have some spotting or bleeding in early pregnancy, and about half of these women miscarry, but if you have an ultrasound that shows a heartbeat between 7 and 11 weeks, your chances of continuing the pregnancy are greater than 90 percent.
Spotting can also be caused by conditions unrelated to pregnancy, for example, because of vaginal infection, such as a yeast infection or bacterial vaginosis. In some cases, sexually transmitted infections, such as trichomoniasis, gonorrhea, chlamydia, or herpes can cause your cervix to become irritated or inflamed.
An inflamed cervix is particularly susceptible to spotting after sex or after a Pap smear, and you may also spot or bleed after sex or a Pap smear if you have a cervical polyp.
Placental problems or premature labor is also causing that some women might be spotting. In the second or third trimester, bleeding or spotting can be a sign of a serious condition such as placenta previa, placental abruption, a late miscarriage, or premature labor. A mucus discharge that is tinged with blood after 37 weeks is most likely just a sign that the mucus plug has dislodged and the cervix is beginning to soften or dilate in preparation for normal labor. You should still report any bleeding or spotting at this point to your practitioner.
In some cases, the cause of the spotting will remain a mystery. It is also important to know if your blood is Rh-negative, you will need a shot of Rh immune globulin whenever you have vaginal spotting or bleeding. It is necessary unless you know for sure that the baby’s father’s blood is also Rh-negative.
Most likely you will not notice any symptoms until about the time you have missed a period or a week or two later. If you are not keeping track of your menstrual cycle or if it varies widely from one month to the next, you may not be sure when to expect your next period. However, if you start to experience some of the symptoms below and you have not had a period for a while, you may very well be pregnant. You could take a home pregnancy test to find out for sure.
The most common pregnancy signs are :
Tender and swollen breasts
One of the early signs of pregnancy is sensitive, sore breasts caused by increasing levels of hormones during pregnancy. The soreness may feel like an exaggerated version of how your breasts feel before your period, and your discomfort should diminish significantly after the first trimester, as your body adjusts to the hormonal changes.
If you feel tired all of a sudden or even exhausted it could also be the pregnancy sign. No one knows for sure what causes early pregnancy fatigue, but could possibly be that rapidly increasing levels of the hormone progesterone are contributing to woman’s sleepiness. You should start to feel more energetic once you hit your second trimester. However, fatigue usually returns late in pregnancy when you are carrying around a lot more weight and some of the common discomforts of pregnancy make it more difficult to get good night’s sleep.
Some women have a small amount of vaginal bleeding called implantation bleeding, around 11 or 12 days after conception, close to the time you might notice a missed period. The bleeding may be caused by the fertilized egg burrowing into the blood-rich lining of the uterus. This process starts just six days after fertilization, but as I already said, no one knows that for sure. The bleeding is very light, appearing as red spotting or pink or reddish-brown staining, and lasts only a day or two. You should let your practitioner know if you notice any bleeding or spotting, particularly if it is accompanied by pain since this can be a sign of an ectopic pregnancy.
Nausea or vomiting
If you are like most women, morning sickness will not hit you until about a month after conception. A lucky few women escape it altogether. However, some women do start to feel queasy a bit earlier and not just in the morning, either pregnancy-related nausea and vomiting can be a problem morning, noon, or night. About half of women with nausea feel complete relief by the beginning of the second trimester while for most others it takes another month or so for the queasiness to ease up.
Increased sensitivity to odors
If you are newly pregnant, it is not uncommon to feel repelled by the smell of a bologna sandwich or cup of coffee and for certain aromas to trigger your gag reflex, which could be a side effect of rapidly increasing amounts of estrogen in your system. You may also find that certain foods you used to enjoy are suddenly completely repulsive.
Hormonal changes in early pregnancy may leave you feeling bloated, similar to the feeling some women have just before their period arrives, which is why your clothes may feel snugger than usual at the waistline, even early on when your uterus is still quite small.
Shortly after you become pregnant, you may find yourself hurrying to the bathroom all the time, mostly because during pregnancy the amount of blood and other fluids in your body increases, which leads to extra fluid being processed by your kidneys and ending up in your bladder.
A missed period and basal body temperature stay high are signs for pregnancy you probably already know to recognize.#