I actually thing that is is a perfectly normal mental response. When we hold things in, the bottle slowly fills up, and eventually explodes. While it may be a more violent than normal response, its very normal to have thoughts of anger due to situations you have been through, especially with harassment of any kind or bullying.

The biggest thing is how you act on that negativity and anger. While you are feeling angry, its best to make sure you can keep those thoughts down and act within the realm of the law. But I am sure you know that lol.