6 months ago a 5 lb rubber mallet fell on my head still pain base of skull neck pain upper spine pain numbness major top right foot minor other limbs?

Yeah...that'll smart. You may be suffering from the residua of POSTCONCUSSIVE syndrome (PCS). I don't know how you were at the type you got hit...for example, from what height did that hammer come down? You could calculate the amount of Force that you took on the head and neck using F=ma but I think seeing your doctor for a referral to a neurologist for possible PCS and management would be a good idea.