So i did my Calculus 1 Final and my instructor thinks I cheated. I did pretty well on the final ( an A) and also the previous test (a B+). My exam marks were pretty shitty at the beginning but they improved over time. I got called into a meeting and he asked me some questions but because I had no idea what the meeting was about and I was unprepared, I was not able to answer the questions correctly and I kept stuttering and struggling to answer the questions. I was able to sort of answer a couple of his questions though. Basically he thinks I had outside help. I told and assured him that I did not. I told him that everything was in my own writing and I submitted all of the solutions on time. Obviously I didn't record myself taking the exam so I can't prove that I was in my room by myself. My grade did improve by like 18% and he says that it raises suspicion. He really doesn't have any proof of me cheating other than the fact that I struggled to answer the questions he proposed to me (because I was nervous af and baffled by the accusation). He told me that he might decide to give me a 0 for the final and also contact the school. I have no idea what to do. I obviously didnt cheat and explained to him that I just studied better for the exam but he wasnt convinced. I've never been accused of any kind of cheating and have no idea what to do. There isnt any proof that I did cheat and I even agreed to our meeting being recorded. After the meeting and once I managed to think straight, I wrote down a couple of his questions from the meeting and did them and sent it to him through email a few minutes ago, but I doubt that will do anything. What should I do? I have pretty bad anxiety when it comes to these things which obviously doesnt help.