cumming inside-HELP

So I'm on my 4th month of birth control next week, but recently my boyfriend and I have been getting a little too excited about the whole no condom thing. We have sex quite often and he cums inside me 9/10 times. I know that birth control isn't 100% effective, which is why I've been worrying so much about pregnancy. I should start my period in 3 days but I'm just too worried to wait.