Pregnancy scare

[Smi128]

hello everyone. To give you some information about my problem, I had unprotected sex the 6 and 7 th of May. I am on birth control and have been for 4 years, I take my low dose combination pills within the same 2-3 hours every night. I never **** a day taking my pill. We used the pull out method, and yes I know this doesn't help much preventing pregnancy just giving you all the details..  I always get my period on the 4th day of my inactive pills. I woke up on the 4th day with really bad cramps and I did start my period; it was red and clotty at times but mostly brown or a really light red/ pink. It lasted about 3-4 days which is pretty normal but my periods are a lot heavier than that. I have taken 3 home pregnancy test, all negative. Should I get a blood test? Could I be pregnant? Would I have gotten my period the exact same time as I normally would on the dot if I was? Or am I just totally freaking out. Please help . Thank you so much to anyone who responds

[Smi128]

Also for some more information I was extremely stressed the month of April with taking finals and dealing with a breakup. The *** above are suppose to say miss