There's nothing you can do about the bump right now, the vet can tell you what it is. Sorta sounds like an abcess to me but that's just a guess. Shedding constantly can be a sign of a skin problem, might even be related to the bump. Mention this to the vet too, he'll be able to look for any problems. Good luck!
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Peter: It's OK, I'll handle it. I read a book about something like this.
Brian: Are you sure it was a book? Are you sure it wasn't NOTHING?