Okay, your just an asshole Anon.. Any time you have unpretected sex you have a chance of getting pregnant. If your periods are usually like clock work and are the same (as mine are not. I have PCOS and they are very Eratic (sp) ) then there is a possibility, espicially if he ejaculated in you. You should probably take a pregnancy test to see. Im not sure if it would be right..depending on when the sex was. But I would advise getting a pregnancy test to be sure or going to a free clinic.