NAH. Your heart's in the right place, and you're right to be concerned and do everything in your power to try and get him to a doctor... but also, he has a right to refuse that service. I hope you'd be prepared to pay for the ambulance you called (if you're in a country that charges for healthcare), since he very much didn't want it. And if you are in such a country, then I can relate hard to him - I know I personally would rather die in that situation than face tens of thousands of dollars of medical debt on top of my car already being wrecked because at that point I'd be in debt the rest of my life and it's just not worth it to me. But even if you're not, chances are high that he was just disoriented and belligerent as a result of the head injury, and thus possibly not even really aware of the severity of the situation and thinking that you were being absurd over "a little headache" or something like that. So really, no assholes in sight.