This turtle's shell looks pretty bad, the soonest appointment at the vet I could get is next Tuesday because I work unfortunate hours, so I was hoping someone could tell me some stuff to do to help until then? He's been acting fine, pretty friendly and his eyes look okay, but I've never had an aquatic turtle (I've got other reptiles). He's already shed a large amount of scutes since I got him and added a new light, so I think he has a lot of retained ones, and possibly a fungus?
Also He will eat worms and pellets, but not feeder fish or veggies, and he's not using the calcium bone, any way to get him to eat new foods?
I've added some pictures of his shell...




