Is my hamster okay?

[Basserole]

I was moving my hamster to a smaller cage while cleaning his prior one, to which he responded by jumping out of my hands onto the floor (about a four or three foot drop.) He landed on his back and made a sqeul, but continued to run around on the floor just fine. He's back in his big cage and will not come out from his bedding, nor can I see any bedding moving around to indicate that he's, well, alive. Should I make sure he's okay or leave him to his own decives?

[GhostsInSnow]

I would check on him, make sure he's still moving around okay, no sign of any blood on the bedding etc. The fall will have stressed him and it may be that he's hiding away until he feels it's safe (i.e when it's dark and/or quiet).
Check that he's okay and then take things slowly with taming. Start by sitting next to the cage and talking to him, even if he isn't about and go from there

[Petite]

I hope your hammy is okay. My ham jumps too, and I find it helpful to entice her into a tube with my hands over each end in order to move her safely.