Well if you used protection then you have a possibility of being preggo cuz' you can even on the first go. ( Personally if it were me I'd get yourself a test then if I were slap my boyfriend upside his head ) Good Luck!! ~~ 13yr old critic Savvy ~~
If you were due to have your period, I would say your chances are pretty good since ovulation takes place right before your period starts.
If you aren't ready to have kids, you shouldn't be engaging in unprotected sex. I shouldn't do this, but I'll give you some pretty good advice: take 2 Tylenol--it'll bring your period on (if it's due) within 48 hours.