AITA for telling my teacher no?

I'm a senior and just turned 18. Choir is a requirement at my high school. Technically you're supposed to take in freshman year but that just didn't work out for me so I'm taking it this year. For Valentine's Day the teacher required us all participate in singing Valentine's. Where someone pays choir and we sing to their boyfriend or girlfriend a song off our list. I said I was not participating. I'm sorry. That's stupid and humiliating. She said it was for a grade and I said I will take the F. We have to do this tomorrow and I have already decided to just take the F. It will only drop my grade to a B. She then started saying if I don't participate I would get an F and detention which wasn't mentioned before. I still said okay. She started tacking on days of detention and when she found out I wasn't gonna budge she stopped. I have 2 weeks detention for not participating and I'm fine with it. My mom said I was being a brat. I don't think I was. I didn't want to do it and feel like she should have just had people sign up to participate in that nonsense like she did the year prior instead of forcing it. So was I wrong?