Two years ago I fell on the edge of a sidewalk and hit the back of my head. I had a cut that was about 4 to 5 inches long. I was so disoriented that I just fell asleep and the next day blood covered my whole head, the mattress and the walls. I didnt get it checked cause I didnt want a doctor to shave my hair. Now 2 years later its healed but it still feel like a bruise and somedays I still feel it pounding. What could be wrong with it and should I spend the money to get it checked?