11 year old cousin got into a fight, couple hours later he falls asleep temporarily, delusional, stressed, unaware, falls asleep again what's wrong?

Head injury: He may have incurred a head injury and concussion. Take him to the ER now to rule out a concussion or more serious problem

Go to the nearest ER: your cousin was in a fight and it appears he has had a significant head trauma. This is very serious and he should be taken to the nearest emergency room. Possible problems could be bleeding in the brain called a Subdural Hematoma and this is a real emergency that needs immediate attention. He is acting differently and this is very concerning. Please be sure to take him to the ER or call 911