How to control my temper?

I got a severe concussion this winter in january and have had a lot of concussion in the past. This one was extremely hard to recover from and I had to take meds to help with my symptoms. Lately I have been really impulsive and on my last impact test my impulse control was off the charts. I have been going a little crazy still not allowed to do sports almost 4 months after hitting my head and cant control my actions at all. Tonight I got so mad at my younger brother I chucked my cell phone at his head so hard it broke into pieces and the screen shattered. I don't know how to control myself I use to never be this impulsive and now its to the point I'm hurting other people. I have also smashed just about everything in my room and my parents are unbelievably mad. How can I control myself? Will I ever go back to the way I was and not so impulsive?