We are vacationing in France and my 18 year old son was out drinking night before last with his friends and slipped on the cobblestones and hit the side/back of his head. His friend says he was unconscious for about a minute. They boys didn't mention this when they came in that evening so my son went to bed and slept 8-10 hours, which is normal for him. He still has a headache. There isn't much of a bump where he hit his head, and there are no cuts or bruising anywhere on his head or body. He does have a slight bit of swelling (I think) at his left temple and continues to have a headache. He rates his pain at a 2-3. We are scheduled to fly to Ireland tomorrow evening which is a 2 hour flight and we are wondering if it's safe to fly. As well, should we take him to a hospital? I might add, this is my one child out of three that has had any serious injuries so I'm a little quick to take this one to the hospital (my husband thinks he's fine); he has had 2 broken arms, a broken nose and 2 broken wrists from skateboarding (he finally gave it up!) and is concerned about flying.Thank you in advance for your advise,Mrs.O'Connell