Yeah, hand feeding will do that to them. Feed nothing but greens for a day, maybe even a day and a half. Then, try feeding again. And only do this if your certain it isn't a sight problem. Make sure he has clear, bright eyes and tracks the movement of the crickets when you put them in, even if he is not going after them. Don't be surprised if he loses them when they stop moving, the younger the dragon, the more trouble they seem to have locating and tracking prey that is not constantly moving. Mine was like a little T Rex for the first couple of months, the crickets would go still, and he'd bounce up on his back legs to try to spook them into moving haha. Maybe try feeding him in a separate container as well, some dragons are very tidy and have issues eating in their enclosure, since it'll make a mess. Mine was like that for a very long time too. I just started feeding mine in a separate rubbermaid, and
bathing him a half hour after, and he has been much happier about not pooping and feeding in his enclosure. Plus it gives you some great bonding times, when they are the most trusting with you. Give it a go and let me know if it works
Good luck!
