I've got a sick prehensile tailed skink and I'm very worried about him. He has turned from a dark olive green collour to paste light mint green-blue on his belly head and tail. The rest of his body has lightened dramatically too. He has also become somewhat listless and his breathing is often shallow. It is sometimes difficult to tell if he is alive when looking into the cage. It doesn't seem to be a heat water or humidity thing. Please if you've got any advice I need it. He looks so miserable.