Could I be pregnant?!?!

Last Saturday my bf and I had some sexual activity I was 33% high chance of pregnancy and he put it in raw and thursted a little and took it out when he took out his penis there was precum. It's now been 5 days and my stomach has been hurting with cramps for a long time it's been 3 hours of pain now. What could this mean? I do have irregular periods. Help!?!?!