about 3 weeks ago i lost my virginity to a guy i have been dating for 2 years, he put the condom on before i even had my pants off, nothing was wrong with it, it didnt late long either, it lasted maybe 3 minutes because i changed my mind and got scared, now i have white discharge, back cramps ( which  i usually get before my period), cramps and headaches ( which i also usually get), he said theres no way i could be pregnant because he ejaculated after he pulled out! but my period still hasnt come im stressing out! is there any chance im pregnant ?!?!?!?!