Protected intercourse, but I am having cramps for five days

Please give me any input that you can. I'm 19 years old in college and my boyfriend is 20, in a different college. We had very protected sex over a month ago (used a condom along with pulling out) 3 days before my last period (it came) I am currently 9 almost 10 days late for my current period. My periods are usually irregular, but for the past three months they've come every 31 days on the spot. I expected them to keep up that pattern, so I was very alarmed when it not come on. I have been cramping on and off for the past 5 days. I feel like my period could come at any second, but there's no sign. The strange thing is, my breasts are not sore. I ALWAYS get sore breasts before and on my period (along with cramps) so it's strange to have the cramps but not the sore breasts. I've been EXTREMELY tired. I can take 4 naps a day these days, and more in between. The tiredness began at the beginning of this month, like 2 weeks after we had sex. When I told my mom about my tiredness, she suspected I was pregnant instantly, which I laughed off. Now that I'm late... I'm very afraid. I thought it may be because of the spring, which is logical for me, but I can't help but worry. My boyfriend and I are relatively new to sex- we just became sexually active about 4 months ago and have done it about 5 times overall(each using condoms+pulling out). But the strangest thing is, the sex seemed to have regulated my period. I used to have super irregular periods, but after losing my virginity, they regulated. Now it's breaking that pattern and I'm afraid. I am scheduled for a blood test in 5 days. There is no way for me to purchase a home test at the moment. Please help!