Hello Jake-22,
I had the exact same thing happen to me when I was in college (I just graduated). I took a service marketing class with a very extroverted professor who put a lot of emphasis on participation. He assumed people who dont participate are not interested in the class topic or are unprepared. Like you I did the work and knew the answers but every time he asked a question, that I wanted to raise my hand to answer, my heart beat would shoot through the roof. Like I just sprinted or something haha. Anyway I procrastinated participating in the class. However, by the end I wanted to challenge myself out of pure frustration with my own mind/body and raised my hand. The problem with me I think was that I felt like I always knew less than the person in front of me whether in a classroom or talking to a friend. I kept implanting the thought that I probably knew more than everyone in the class and that helped my social anxiety. I thought about speaking in front of people in all the wrong ways. I always thought that I needed to sound interesting, smart, and impressive. Now I know that thats never going to happen if I sit silently. A few times I said things in the wrong way and to my surprise no one laughed I just continued and fixed the sentence up and people were impressed with the thoughts I had. So its okay to speak and then take a minute to put your thoughts together again people won’t judge or make fun of you. Expression takes practice. I used to imagine conversations in my head to practice or even speak in front of the mirror (I know it sounds crazy but the practice helps!). The only thing I regret not doing is not talking to my professor. I didn’t want him to misunderstand my silence for not caring about the subject but just as something thats a challenge for me. I think people are too embarrassed to address these issues nowadays. I still find it a challenge to express myself but I try to do it anyway and I stopped caring about what people thought about how I spoke because it was better than them thinking I didn’t like them or was not interested. I had my fair share of people who misunderstood my silence as lack of interest or failure to care but in reality it was the exact opposite and now I dont have them in my life because I never told them just how much I cared. Im trying to change and improve by changing how I thought about them and this takes time. I figured if insanity is doing things the same way and expecting different results than thinking of these issues in the same way and expecting myself to breakout of the cycle is insanity too. So I changed how I thought about my issues and that helped change how I acted. Anyway my rant is over haha, hope this helps! Best of luck!