Hi, Four Days Ago I Fell Down The Stairs And

Hi, four days ago I fell down the stairs and landed hard on my tailbone. I now have been having sever headaches and neck pain for the last four days and pain relief doesn't help. I have had bouts of nausea and a little dizziness. I can only lay down comfortably, I I walk around or sit it hurts badly all through my head. The neck pain is all at the base of my skull and the headache is all over. Please advise