Bleed after sex 5 days before period

Marina

We had sex 5 days before my period. It didn’t hurt at all. As soon as we finished we noticed I was bleeding (thin, pink) not a lot but decent amount. I didn’t end up bleeding after that though. This is the first time it’s happened to me. Is this normal? Has it happened to any of you ladies? Worried it’s pregnancy or endometriosis, but hoping its just normal uterine bleeding.