I've been through something similar.
Self blame is perfectly normal because you feel like even though you were I'm such a state you could've done something. It's so difficult to listen to reason and logic when guilt is playing such a huge role.
I tackled with self blame for 3 years, still do, even though I know "logically" what happened to me. Had I have been sober, I wouldn't have let him take me to his house, let alone anything else. And neither would you.
My suggestion would be to go to a doctor and speak to someone, they will examine if you're injured in any way to find out why it hurts and likely refer you to a mental health nurse (don't let that worry you), as this is going to have a huge psychological impact.
I confronted my attacker and reported him to the police but it went nowhere, making me feel even more that it must've been my fault.
Its going to be hard telling your boyfriend, which is why I suggest you talk to a professional first.
You will be ok.
