Condom pop

Hey guys, let’s get to the story n questions so Friday night me n my boyfriend had sex but he was just playing with my (VV) using his penis but he was putting it in n out without a condom so basically teasing me of course he’s horny so prenut so he finally put a condom on n after multiple positions it pop while he was hitting it from the back but what makes it even worse he was high so he say he doesn’t remember if he nutted or not but here come the even worse part my cycle came on Saturday n I was suppose to take a plan b is it to late ? I did research they was saying it can mess my body up if I take it while on my period so is it true n give more info if you like please