Sex issue

I need some help.

So, I’ve been with my boyfriend for 8 months, we haven’t had sex in about 3 months, and last night when we had it, it hurt bad and after I went pee I seen blood like I lost my virginity.

Let me remember y’all, I slept with my ex before and I lost it to him. When me and my boyfriend got together it didn’t do it until last night. This morning me and him did it and I’m kinda hurt but no blood. Anyone can tell me why I started to bleed and why it hurt?