4 days ago a guy ran into me and hit the right side of my head with his shoulder (he was taller than me) I was ok afterwards, no memory loss or nausea, except for a headache. I thought nothing of it and went home. Now I wake up everyday with a headache, pain in my neck and feeling dizzy. As the day progresses the pain and dizziness go away, but cycle starts again after I've woken up. Should I be worried?