Idk if I'm pregnant?

You last had unprotected sex on the last day of your period, which depending on how long it lasts could be day 5-7 of your cycle. It is possible to become pregnant at this time, but it's is one of the less likely times of the month. It would now mean you are at around day 12-14 of your cycle, which is usually the time of ovulation and your most fertile time of the month. With this in mind it sounds to me like you may have ovulation spotting not to be confused with implantation bleeding - which if it does occur is most likely to be the week after ovulation; for you this would be next week.

There are a couple of thoughts on what causes ovulation spotting. Some people believe that the light spotting is a result of the egg rupturing through the follicle during ovulation. This is why some women may notice brown spotting.The other possible explanation is that the spotting is a result of changing hormones during ovulation. As your body prepares to ovulate, follicles will start to grow and mature. As they mature they produce more estrogen. This increase in estrogen triggers a surge in LH, another hormone involved in ovulation. When LH surges it signals the mature egg to burst from the follicle. Estrogen rises sharply right before a woman ovulates and it is thought that the increase in estrogen levels may cause light spotting to occur.

I hope this helps you<3