My son crashed on his mountain bike yesterday evening and he believes he was unconscious for a brief moment, but after some research on his phone calls to me I believe he was probably out for at least 5-10 minutes. He has swelling and scraps on one side of his face from where he hit when he crashed and now his eye is starting to swell and is showing some bruising under it. At first he couldn't remember how he crashed but it did come to him after a couple of hours. He's had no headaches, no vomiting, no bleeding or fluid coming from the nose or ears and hasn't felt dizzy or disoriented except for right after the initial impact. My question is if we wait until the morning to seek medical attention is that going to be more harmful for him versus going to the ER tonight.