I got accused of cheating on exams by my teacher when I didn't

So today after class I got pulled aside by my teacher and he accused me of cheating. He basically said that he knew I was a cheater and that I cheated on his exams and that if I didn't admit the truth to him, he would take this to extreme levels and go even further than just simply reporting me. Also due to the fact that this was after class, his next class would be coming in and he pressured me with time. When I wouldn't answer trying to find the words to defend myself he kept non-stop talking and threatening me if I didn't admit to cheating, barely letting me talk. In addition, he also said that I was dumb for thinking he wouldn't notice because "Someone like me who doesn't usually score this high, scored very high on the hardest exams. You do well on multiple choice but there is no way you get that high of a score on 1 section and completely fail the free response". I was having a panic attack and almost cried when he kept persisting, and I ultimately gave him the response he wanted which was that I "cheated". He wasn't accepting a no from me ever. And for the rest of the talk he just kept saying he was angry and disappointed and that he wanted to change my grade to failing and report me and I just sat there quivering and scared agreeing with him saying that I was ashamed of myself and he has the right to be mad at me. I really wish I was better at standing up for myself and controlling my fear. So to give some background info: I am in this business/financing class at my school and I am not the best at it. I usually score average with just passing grades on my exams. It is my 2nd semester now and I still continue(d) to struggle. We have 2 sections on our exams, one section that is like circle the correct answer from these choices and the other section requires us to freehand it, basically like free response questions. I usually do better on multiple choice and because I practice them more. This semester, our teacher warned us that we would have 2 difficult tests coming up due to the content of the unit. I was already scared as my grade is like a 65 in the class and I needed it to go up so I studied my butt off for those tests. It kind of paid off since I scored very high on the multiple choice section as compared to my previous multiple choice scores. Unfortunately I didn't do as well on the free response for both of them, making my overall score for those tests about an 80-85. I was able to bring my grade up a bit though. Unfortunately, we would be having our ultimate finale exam for the semester a few weeks later which our teacher said would basically count for a good portion of our final grade. I completely bombed it, as I was stressed out, didn't get enough sleep, and my mind was pretty shitty and mentally unwell that day(something I have always struggled with). Scores came back and I did a pretty bad job on it, on both sections(my class grade is at least passing though). But something I didn't know was that he had actually gave me a different multiple choice section than the rest of my class, which was a copy from a different period but the same course/same material. So now that I didn't do well, his conclusion is basically that I cheated because I scored high on multiple choice sections when I usually never score that high, meaning that I copied from other people around me. According to him, this was why I scored horribly on the multiple choice for the final exam, since I had a different copy and could not copy off of others