He does indeed have a bright smile! I'm not sure what the weirdness is behind him though. Did you select that area and darken it? It kind of upstages your good work in front.
Wonderful vibrant and compelling subject ! His smile and energy are infectious and make this image very compelling. You could just feel it looking at him. What happened to your background, though??? I think you used too much flash. Try a slow synch flash to get the background, next time. Well done! 8