lol happens all the time when they bite things that they don't eat. Their jaw is very much different than what ours is like and the bottom acts independently to each side only linked by skin and maybe a slight piece of cartlidge in some cases. When they miss bite it seems to knock one side of the jaw to the side sometimes. But after a couple yawns he'll be fine. If it really worries you, if its close enough to feeding time give him a meal and it'll straighten right up.

On a side note - you need to push through the striking while it's young. My mainland male from Bob Clark was quite tub aggressive when I first got him. I took my bites, and worked with him regadless as much as possbile. Now, as long as its not feeding day I can just open the tub and pull him out. Best to get him calmed and use to you now before the real damage can start.