Eye problems can be the result of a irritation, or improper environment or care. Dehydrated animals are more prone to eye infections, as are animals that are receiving improper amounts of supplementation (too much or TOO LITTLE). your chameleons eyes do not look sunk in from the picture but sunk in eyes are a sign that your chameleon is not getting enough water. Eye irritations can also lead to skin infections (due to constant rubbing) so watch your chameleon closely he may be irritating it more by rubbing on objects in your terrarium, this can result in an even worse skin infection around the eye. Also you said you were using a qtip on the eye, this might not be a good idea because tiny fibers in the qtip could get in the eye and cause more irritation , i would recoment using a CLEAN seringe.