We are going through this right now. My 10 year old started having trouble last October after going to a friend's house and watching a scary movie with clowns. Since then, there have been other "images" that seem to cause him to not be able to fall asleep. We have a fish tank in the room (for light), he sleeps with his 11 year old brother, we have a security system, white noise, prayer, positive imaging (ie; a happy place), watching funny cartoons,etc. We tried everything. He'd get himself so worked up! After a couple teary nights, I asked him what he thought would help and he said he wanted to go to a doctor to find out what was wrong with him. I assured him there was nothing "wrong" with him, but he was so upset, that I told him I'd check into it the next day. My 10 year old is NOT the drama queen that my other kids may tend to be. When he said he wanted to die cuz he was so frusterated, you bet your butt we took steps to get it figured out. He slept on our bedroom floor until we got him in to a counselor. I thought maybe there was some "magic trick" that I hadn't thought of. Not really. The counselor told us we'd already done pretty much everything she'd suggest. Then she told us we may want to look into anti-anxiety meds to help him before bed. My SIL also took her son to a counselor for the same problem and when I asked her what finally helped, she said she'd give her son Benadryl an hour before bed to help relax him. That really wasn't the route I wanted to take, but at some point, you get desperate, ya know? She suggested a "Fear Box" -we write down our fears and put them in the box. We then take the box out of the house. Also, she had my son draw a picture of the scary image. He then drew a picture of the exact opposite. So, he drew the "scary clown", then drew a very "happy clown". We did this in the daylight so that we were able to talk about it well before bed to try to alleviate the nighttime stigma. We also got him some books that he really likes to read/look at. He does this right before bed while I'm getting into my pj's to head into the room. Last but not leat, I told him that I'd buy him a new Lego set if he made it 3 weeks without coming into our bedroom. So far, so good and it's been 4 nights.
I realize that kids can have active imaginations and some can get more "animated" images-so much so, that it's hard to get the vividness out of their brains. Many nights, as I lay in bed, my mind will start racing...thinking about so many TO DO items, that I can't get to sleep. It's much like that, only scary TO DO lists!!! LOL! Try to be patient with him. I'm sure he's not exactly happy about being scared or full of anxiety. Maybe some of our counselor's suggestions will help. Hopefully, it's phase and soon he will be falling asleep on his own. It could be that the adrenaline from football is hard to come down from. Maybe a bath instead of shower, if that's what he's doing. Tell him it's good to soak his muscles after football!! :) *Oh yeah, my daughter has this issue, too, only not as intense or often. What usually works with her is to have her tighten all her muscles.....eyeballs, down to her toes. Hold it for a couple seconds, then slowly relax each muscle one by one. My mom did this with me when I was a little girl and I use it today. It gives the mind something to think about while tiring out the body. I wish you luck!!! ( and sleep :)