My Cat, Dumbdumb (yes, that's his name) is not himself at all the past week. At first I just thought he had a cold or allergies. But then I started noticing that as every day goes by he moves slower and slower, eats less often, and sleeps more. Also, His hair is falling out. No, this is not shedding at all, his fur is getting so thin you can just about see his skin through his fur. Nothing like this has happened before and I don't know what it could be. He seems fine aside from moving slow, sleeping a lot more than usual, and his hair falling out. Any ideas?