When I Run Or Jump Or Otherwise Move My Head

When I run or jump or otherwise move my head it feels like my brain is moving around inside my skull. It feels like it is somehow loose in there. It feels a little bit like I get a punch everytime I jump and my brain crashes into the skull bone. It also hurts if I shake my head or if I go with the car over a bump in the road. Maybe it is my blood moving around in my head that I feel. I have had this for a long time but I still remember how it felt like to be healthy.