Why would a teacher be mean enough to send a student to the back of the clroom for the rest of the year?

One day in Spanish cl we were playing a game with two teams when we were conjugating verbs in the preterit tense in the Spanish. We were tossing the ball to each other, and seeing which team could conjugate all the given verbs in all conjugations correctly first. I accidentally threw the ball when she said not to throw the ball, but I didn't here her say to not throw the ball until I had already thrown the ball. Then she told me to sit down. I can sort of understand that. Then another say when we were announcing vocabulary words in Spanish I called out "la banana" when she said la ganga. She then gave me an after school detention. I find it weird that she would give me a detention after school if other people were talking too, but at the same time I was doing all my work. It's weird she would single me out like that when she knows that I'm a straight A student in her cl. I attended my attention, and apologised, but then the teacher said for the rest of the year I have to get seated in the back of the clroom. Isn't this stupid? Why should a student be demeaned of their basic rights and be sent to the back of the clroom for the rest of the year when you could work just as easily in another seat? The teacher automatically umed I was going to call out yesterday, but I wasn't. It is demeaning to not be able to sit with other students because since I am a bright young man, I can help other students, and at the same time be sociable enough so that Spanish class is fun. I told the teacher this, and told her that I couldn't see the board very well, and she wouldn't consider changing my seat. Sure, changing your seat would have been nice, but sending me to the back of the classroom away from my piers is a violation of being a good teacher and is really insulting and demeaning to students such as myself. It's kind of weird that a girl that I've hard previous conflicts with would just go to another seat and sit in my original seat, but I have to do to the back of the classroom, when she calls out too. It's almost like saying that I'm less important than that other student. What should I do about this. I don't know if I can wait much longer just being in the back of the classroom being secluded from my classmates. Do you think the teacher should have sent me to the back of the classroom? Seriously, this teacher needs to get a life. Thanks.