Could I possibly be pregnant?

So my period is a week late now, and my boyfriend and I had unprotected sex about three days before it was supposed to start. I'm not sure if it's even possible to get pregnant that close to the date?? Anyway, He did not ejaculate inside of me, but when he came we also didn't wipe the excess sperm off of his penis before he stuck it back in. I've been cramping here and there the last couple of days and I keep thinking it'll come but it hasn't came yet, should I give it a couple more days before I take a test or??