Something very similar happened to me a few days ago. It’s been a month since I started school again, was called on in one of my classes. That teacher already knew I had a speech impediment/severe stutter. I was called on to answer a question in class, and I knew the answer but couldn’t say it. While I was trying to say it, I just had a block and stutter. Everyone was just there rather laughing or giving me a weird look. Ruined the rest of the day for me, and I don’t feel comfortable in that class or any class. I’m still in High School, thought people would be more mature by now. But clearly not, and doesn’t seem like people are going to change.