It sounds like it could be a concussion - he will slowly heal if he does not
see a doctor. I got hit in the head with
a softball
a few years ago and was very dizzy, nauseous, and had a headache. I did not go to the doctor.... found out 2 months later (after the feeling was starting to come back and I got black eyes) that I did indeed have a mild concussion and had to go for a CT Scan for possible nerve damage. I still do not have a lot of feeling in the spot that I got hit.