Definitely sounds like a respiratory infection. He needs to see a vet ASAP. Respiratory infections are the #1 killer of reptiles!! They are very common and totally treatable with antibiotics. Just keep him warm and comfy till you see the vet.
You really need to see a vet...Reptiles get sick slowly and heal slowly.. If your luck you will have caught in time to not have done to much damage..I really hope he gets better..
