You don't feel nothing. You just had to suspend your normal feelings in order to get through it. Those feelings are there inside, though. They're just waiting to come out when they are really sure the coast is clear.
Anal sex can be painful at the best of times. I don't know if it hurt you. For sure it humiliated you. For sure the process of him doing that and being inside you in that way and using your body like that, and being aroused while you suffered and had to comply, was something that shocked you deeply. But you complied and lay still as that was the best way to get through it. But to be present through it, your mind had to switch your natural emotions off.
Because you found yourself in a situation where your emotions were not important. In fact, where riding roughshod over your protest was a pleasure.
And there's probably something else in there too which is uncomfortable to look at. You wanted to please him. You wanted him not to be angry with you. You wanted to appease him. You didn't like the feeling of him being angry with you. You knew it was wrong of him to get angry about your contact with the man he didn't like, but it was still your instinct to appease him. So that was another reason to let him do what he wanted.
And that's what I think is worrying you. It was your conscious decision to let him, in the end.
So is that not consent? You let him. No, it isn't. IT ISN'T. Your alternative to 'letting' him would have been to escalate his anger by resisting. You'd have had to make a real fuss - try to escape his physical hold, cry, shout, whatever. Just because you didn't do that doesn't mean you wanted him to have anal sex with you.
Consent isn't allowing someone to do something you don't want them to do, after you've told them no. That's not consent. So please, please get that straight with yourself.
Consent is saying yes and meaning it.
Sometimes people are in a situation where they even say yes but don't mean it, because saying yes is the safest and quickest way to get through it. Sometimes they have to feign pleasure to satisfy the other person so that it will be got over with and stop. Sometimes they even have to have an orgasm for the other to stop. They have to go somewhere enough in their head to, in a situation of non-consent, have an orgasm to conclude matters.
You feel so sad because you have been attacked, and by the person you trusted most and had let closest to you. And because you have lost the man you thought he was. Lost your boyfriend. Lost your future with him.
You've been attacked, your boundaries trampled, your trust broken and you've lost your boyfriend. And you're worried it's your fault, because you 'let' him.
Dear OP, poor OP. You know it's not your fault. And you didn't want to let him. And your sadness is grief for everything that was lost.
I am not sure what outcome you'd get from trying to have him investigated. I'm not sure if the process would be helpful for you. I understand why you want to forget about it.
You know you must break with him completely now. Because this is about the time in a new relationship where the bad starts to come out. And this is bad.
I feel like you should get some support. Maybe even go to a sympathetic doctor and be checked. Bleeding isn't ideal. Maybe part of you has been ripped. I think start with the doctor.
I'm so sorry. Just take heart from what people here are saying, and their warmth and support for you. What happened was not your fault - you did everything right. He's the wrong one. Xxxx