Sleep for more than an hour, wake him up and make sure he can give you coherent answers, if he can’t get to the ER right away.
If he can give coherent answers, let him chill, no tv, no bright lights and some headache medicine but not to much.
Schedule an appointment for cognitive testing, it’s better to have a baseline before a concussion, but you can have him test and do follow up to make sure he doesn’t have any lingering injury before he is allowed to do any physical activity again.