We have a very old cat, probably about 16 years old and used to be happy being more on his own, more antisocial until recently this past week he will meow constantly until I come and pick him and hold him in my lap. After holding him awhile I can put him down and he will sleep in the same room as us and be fine. This is new but we just thought that for whatever reason he wanted to be with people now. Once and a while when I was holding him he would make these funny noises, maybe a cough just once or twice. I noticed this morning that he really hasn't moved much from where he was last night and this evening I noticed that he hadn't eaten any of his food. I put the food and water in front of him this evening and he really didnt' eat but a few pieces and drink a little water. He does not seem himself and he did bring back up what little stuff he took in this evening. Any idea what is wrong? How long should I let this go before I call the vet?