I know when I first lost the ability to control my mental health that anger became prevalent, sometimes inner rage describes it better, fortunately medication helped me a great deal, maybe you could speak to a dr about your feelings?
Who you want to kill? Someone special or just random people? It's normal that you want to revenge your bad feelings to others, especially if there are some who are responsible of them. I know it's not easy because I've felt the same, but try to release your anger somehow, other than violence. Don't take innocent people with you.