How Can Head Pain Caused By Trauma Be Treated?

my head seems to hurt now and then. well a guy ran in to the back of my head last month and its been happening now and then since then. Its mostly the left and the back side of my head and the right side. When its major it hurts like some one slapped the back of my head 3 times and when its minor it feels like some on is zapping me with a electric shocker. OH! also its worse when im more tired.. thanks!~