Sex while on my period

Last night my bf and I were at home hanging out, things started to get a little hot and heavy. He knew I was on my period and at first he was kind of iffy about the whole having sex while on my period. He then agreed to it, so we started to have sex and he was just acting weird about it. It almost seemed as though he felt grossed out. He didn’t want to touch me, he finished within a minute and got up to go to the restroom. idk if i’m just overthinking it and being over dramatic but it made me feel self conscious. Idk? What do y’all think. Has this happened before with your partner?