Girl's Behavior

My daughter got into a fight with a group of bullies, not sure how to react?

My 8 year old daughter can be very angry like any child, but she has never beat anyone. Recently she told me that some classmates were annoying her at school, and she did not know how to handle the situation and I said: “Just because they are older then you, doesn’t mean they can bully you.” “but the two are much bigger than me.” “I bet their balls aren’t” and we both laughed. The next day, the school called telling me that my daughter had gotten into a fight with two boys, from what I understand one of the boys was saying something to her and she kicked his genitals, causing him to fall to the ground. She kicked his hands away from his groin and stomped on his privates, at which point the second boy tried to separate the two. Then she grabbed the second boy’s testicles and squeezed, which I taught her to do in case a stranger ever tried to assault her. A teacher had to literally pry her hands off of the poor boy’s testicles, since I told her to never let go until she felt them give (which fortunately never happened, although the boy was sent to the hospital). I don’t know what to do. Obviously teaching my daughter self-defense is important, but how can I teach her that she can’t use these techniques in mild situations such as these?
My daughter got into a fight with a group of bullies, not sure how to react?
Post Opinion