Should I take a Plan B

so my man came over just now and we had sex with a condom and he came on my boobs and then we snuggled for a while and we started making out and got turned on again and his dick went in me VERY momentarily he did not cum in me. we're worried about dried sperm from cumming earlier or precum impregnating me. I just finished my first pack of birth control pills and my period is due to come soon. should I put myself through plan b for peace of mind? or should I just try to calm down and wait for my period?