Bloody sex

So it’s a new relationship. Maybe a month or two. We’ve had sex a handful of times, and now I’m afraid to because there’s been two times where I’m just like BLEEDING and I don’t know if it’s because he’s too big or what’s going on. He’s really nice about it, like doesn’t super freak out other than prob thinking he broke me lol. But I’m terrified that like...is it me? What am I doing wrong? This has happened before with other guys like occasionally but I don’t know why.