Is it normal to feel happy when an annoying person fails?

There is an older lady in her 50s, who has been in university with me for the last couple of years. She was studying to become a school counselor. In class discussions she'd always give wrong or strange answers, and outside of class, she had strange attitudes and was very inconsiderate. It has nothing to do with a generation gap, because there are a few other mature students who are much more "normal" and likeable.

I never thought she would make a good counselor, it bothered that she was even in the program. So when I found out recently that she was not accepted to the practicum, I was really glad! I feel badly about being happy that she has failed. But at the same time, I would pity the students who had to endure her weirdness. Is it normal that I feel happy at her failure?