Or stupid?

I used to be an ace at school. I always got like 90s, high 80s, and whatnot. During the first semester of grade 11, I got high 90s.

Then something happened. I think I just became lazy. I used to be OCD about school; I always feared that if I didn't do well, someone will die in the future because of mistakes made by me. Nowadays, I think "I don't want to be as unhappy as I was during that time". So I don't really look forward to school anymore. I don't put too much work into it.

I do have some good things to say about myself. I'm very well-spoken and articulate in writing. I am very polite, and soft-spoken. I am considerate to others, and despite my anger with the world, do things to help other people. People think that I'm good, socially.

Am I really "dumb"? That's kind of what my friends think of me.