Help! 😨

I recently had sex with my boyfriend and he admit that he went inside me (we had unprotected sex and I'm not on any birth control we also had sex on my second day of my fertile window, my period won't start till the 20th of this month) it's almost been 72 hours and lately I've been having cramps and this feels like period cramps and it feels like stuff is coming out but I checked and nothing. I'm scared girls help a girl out I need some answer 😩 am I already pregnant??