I know that you just got your guy not too long ago from someone else and you've been having a few problems. The first thing that pops into my mind is have you had a fecal exam done? They're usually really simple and I don't believe that you have to have a reptile specific vet to do them. I think that would be an excellent idea. Of course if your baby's not eating then not much is probably coming out. In that case you might seriously consider seeing a vet. When lizards do anything that doesn't seem normal to their species or them as individuals it's a good idea to seek out an experienced herp vet for at least some advice.
Turst me on this. Blake started biting his tail a few months back and I decided to take him into the vet because it was totally weird that he did that. It turns out that it was a good thing that I did. There was something wrong with a nerve in the way his tail healed from an old accident. Something happened to further irritate it and the tail started dying. The vet told me that if I hadn't brought him in and had the surgery to amputate the tail, it would have progressed to the point that it would have eventually killed him. Just something as small as biting his tail, something that he had never done before.
So I would at least call a vet and get their opinion. Most of them are more than happy to help you with advice.
Lindsay