PREGNANCY SCARE

Hello everyone... I honestly need you guys help before I go buy a plan b! Saturday night my boyfriend came into town an Being that he lives 2hours away we had A LOT of “ I miss you “ sex. So basically we had sex Saturday night and Sunday morning. Out of all the times we had sex, he nut inside of me TWICE. I ran to the bathroom all both times to try an get it out but not much came out. I say all that to ask this, today I started spotting & it’s time for my period to come on. Can I possibly be pregnant in the next 2 weeks? Do I need to take a plan b being that my period came out 1 day after having unprotected sex?