Never bitten by a cham, but my Bearded Dragon bit me a couple times. She seems to be incapable of seeing the difference between my fingers and her food.
What is your supplementation schedule? It is possible to over supplement. Also, I don't think you are using the correct supplements. You need Repcal with and without d3 and a multivitamin. Do the legs or appear bendy at all? Can you get pictures of just the legs?
Chameleons are not exactly a beginners pet. As stated above, they require a lot of care, and can not be handled, so if you want a handleable reptile that is easy to care for, a chameleon may not be the right pet. However, if you feel you can handle having one they are amazing pets.