I Didn't Understand - Trigger Warning

We always acted like that. I thought that was just how he was. The flirting, the looks, I didn't think it was anything special. I'd had a little crush on him, but he was my teacher, what could he possibly want with me? So Social Studies wasn't my best class, but it was nothing a few study sessions after school couldn't fix. I usually did well in his class, but usually isn't always. So I stayed after. Just a little study date. As soon as the bell rang, people set off for the busses, their cars, or after school programs, while I walked to his room. When I arrived for our study session, I interrupted a little makeout session. I just watched them for a minute, I was curious. Then I knocked on the door and a student, a senior now I think, looked at me. I couldn't tell whether she was angry or relieved. I walked into the room and put my backpack beside my desk. Two hours with my favorite teacher couldn't be so bad. But it was. It was awful.
We chatted as usual, flirting and still working. He pulled up a chair and sat right next to me at the desk. I didn't take notice of it, it wasn't unusual. He pushed his chair closer to me. And closer. He whispered in my ear that I was beautiful, but he thought I'd look better WITHOUT my clothes. I blushed and just brushed it off. It wasn't like I'd never had a guy try to take me to bed before. He pushed a little bit of hair behind my ear and came a little closer. I moved away from him as he moved toward me. Stop, I told him, I don't want to do this. He told me to come sit with him, but his chair was only big enough for one person. I shook my head and tried to keep working. He literally picked me up, and threw me down onto his lap. I cringed and bit my lip only so I would not scream. He whispered in my ear again, he told me I was going to like what he was going to do. I was shaking my head and almost crying though nothing had happened yet. He started trying to unbutton the school-uniform shirt. I pushed his hands away; or tried to at least. At this point I was trying too hard against him, so he just put his entire arm on my neck until I was unconscious.
The sound of the school bell, for the last bus, woke me. I called my mom and asked her to come get me. When she asked what happened to me, I said I got in a fight with a couple of Bayview kids. When I got home the first thing I did was take a shower. I could see so many places, where he had bitten me, that were red, and I had bruises all over my ribs and arms. I didn't go to school the next day. Or the day after that. I was sick to my stomach, and I couldn't bare to see my friends. I just laid in bed for six days, crying. I wasn't hungry, or thirsty, or tired. But all I wanted to do was sleep. I told my mom I had the flu and I just stayed home all week. He asked me why I wasn't in school. I said I was sick.
I couldn't tell anyone. I still can't. They wouldn't believe me in a million years. Sure, I've never lied to the school, but he's a teacher, of course they would take his word over mine. I don't know what to do anymore. I've seen a counselor but I was afraid to tell them what happened. What should I do??