[Maker]

That does look sore, I would run your hand everywhere in his cage see if you can find anything sharp. In pain they are likely to still eat and drink, they are prey animals and won’t give any signals of being ill, it would make them an easy target in the wild if they did. I would talk to my vet and maybe send them a photo, I would worry if it became infected, got red, hot, oozy, smelly, you would need to act quickly if this happens as they go down hill from infection quickly.