Endless cramps

So i am sexually active and a little while ago my boyfriend and i had had sex twice with a condom then 2 times without a condom plus him pulling out. He said he barely had any cum the last two times. I started birth control forgot to take it for like 3 days then started up again like 2 days before we had that sex. So i have had these cramps that are sort of present but not too painful since and been more hungry than usual. Could this be the birth control or pregnancy?