atp , idk if i'm overreacting orrrrr

ok so , on this past sunday (02/23) & valentine's day weekend , my boyfriend and i had unprotected sex and i was supposed to start my period the 22nd which was late , i thought it was late because of valentine's day because that was the only other time i had sex around that time of the month , anyways i took the plan b on the 23 because he believed he nutted inside and now i'm 8 days late , i'm waiting a couple more days to see if it will start but after the 2nd week , i was gonna take a pregnancy test ! ANY IDEAS