the er will do what you did. check pupils, make him do a few phsical tests, walking and so on and then send you home to monitor him for 48 hours. my daughter did have a concussion and this was still the result with longer monitoring than the 48 hours they give you if no concussion. The extra tests (cat scans) they told us increases the risk of childhood cancer and knowing she did get knocked out and threw up they still said since she was acting fine they if they were M. they would opt not to do the cat scan unless something new developed
BTW my daughter had no external mark when she was hit on the head...the bump is actually good. It means the swelling went outward and not inward. Be prepared to cry and worry for the next 48 hours! Follow your gut. It cant hurt to take him in, but they will probably J. send you right back home
BTW limit pain meds for fevers or atleast call your doctor and see which ones are safe I believe anythnig by tylonel is dangerous in a head injury because if there is internal bleeding it make sit worse