Idk what to do

I don’t know what to do. I’ll get straight to the point. My ex bf raped me. It wasn’t, how it felt at the time, in a malicious way or at least I didn’t think he wanted to hurt me, he was always so nice and caring. Or so I thought. We were in his room ( we’re both 16 and had both been sexually actively together for 3 months) (5 month relationship) he had previously been in a year long relationship and was sexually active. Anyway, we were in his room and, like couples do, making out on his bed. He asked me to take my jeans off but I said no because I had to leave soon and I knew what it would lead too if I took them off. Anyway, it was kinda hot in there and he already took his off so I thought why not? So I did. I made sure I kept my underwear on so I wasn’t giving any mixed signals. We kept making out and things started getting a little heated so I told him that I didn’t want anything to go any further and he said that’s fine. We kept kissing etc. And I said again that I didn’t want to have sex but then he said ‘but we haven’t in weeks’ and then proceeded to beg me but I refused and told him that I wasn’t in the mood so nothing happened. So we kept kissing and things got more heated and I could feel that he had a hard on as he had only boxers on. He then started to put his hands on my underwear and started to pull at them. I knew exactly what he wanted but again, I said no. He then pulled down his boxers and moved my underwear to the side so he had access without taking them off. I thought he was going to stop, I had faith that he wouldn’t go any further and that he was just teasing but no. I thought that in this situation I would of pushed him away. But I didn’t. I was so scared. I thought he cared about me. I guess I was wrong. I’ve never felt that way. He’s a 6f 3 guy so I felt helpless. I thought he would stop but he didn’t he just kept going, and going. He looked at me and kept going. That’s what hurt me most.

After this I realised that he’d done it to me before. I’d just not realised it. He would make me feel guilty and have sex with me without protection when I said no. I guess I didn’t think it was rape because I let him to it to me. Before I didn’t put up much of a fight. This time I made sure I did but he did it to me anyway.

I don’t know what to do. I want to tell my mum but I don’t know how. What can she do anyway? I thought I was ok and that I didn’t need help but at the moment I’ve started to realised maybe it’s hurt me more than I thought.