How much time does a hamster injury need to heal?

We dropped our dwarf hamster from about 5 feet onto carpet, he was stunned/unmoving for about four seconds. He injured his right arm (not sure if at the wrist or joint), and didn't put weight on it at all for three days. Two days after that he was only just starting to put it down when he walked, during this time we accidentally gave him too much asparagus as a treat and he became sick with yellow diarrhea and had very little energy. Today, just over a week since dropping him he has his normal inquisitive energy back, the asparagus lump in his belly is gone but he's still bloated. His bottom is clean so I don't think he has the runs anymore and he is weight bearing on the hurt paw.

Can he go for a run in his ball yet? He used to spend over an hour in it each day he loved it so much, but I don't want him getting hurt. Thanks - will choose a best answer.