Why did it hurt?

Naylani

Okay so a couple of days ago me and my boyfriend were in the mood and were about to have sex and he tried putting it in me from behind but for some reason it hurt like a lot and its never felt like that before so we tried a different position but literally every position we tried besides him on top or me on top hurt but then 3 days later I got my period? Did it hurt just because I was about to get my period??

Anyone else with a similar situation?