Is There A Possibility Of Conceiving During First Intercourse While On Contraceptive?

hi I.m 17 and have been on birth control for almost 2 months now im on the last week of pills before i start my new pack. at the beginning of my 6th week i had sex for the first time and my bf did not wear a condom. my question is should i worry or am i stressing for nothing. i've never missed a pill and have taken them always at the same time