[Hammy992]

If your hamster flinches when you touch him then he is in pain. The foot being purple could be that the area is swollen and bruised from injuring it in the fall, there might be broken bones or the blood flow to the foot could be restricted which can be quite serious. I would definitely take him to the vets for a checkup, they can do an x-ray to check if there are any broken bones and give him some pain relief.