Had sex last july 17-19. had my period last august 5-9. im 2 days delayed right now. is there a chance that i'm pregnant?

Pregnancy: If you had unprotected sex and then had a normal period then it is unlikely you are pregnant. However it might be that what you thought was a normal period could have been implantation bleeding which normally occurs 6-12 days after conception close to the time when the next menstrual cycle is expected. It is usually just spotting but can be like a light period. Get a pregnancy test.