11 year old cat not eating - PLEASE HELP US!

Question:
 Greetings, I am going inane trying to figure out why my 11 year old cat has stopped eating. He was absolutely fine last thursday, his normal crazy self and was eating like a pig like usual. Then friday evening it seemed like he was breathing a little harder than normal and looked a little tired as well. Sounded like a little weezing too. And i noticed these strange contractions in him that i haven't seen before. Like he was cold & shaking a little. The entire weekend I monitored him and tried my best to get him to eat, but he just hid in a closet all day and wouldn't even consider food or water. Monday morning I brought him to his regular vet for an emergency appointment and they gave him an antacid shot, hoping this would calm his stomach. Nothing changed, he still wanted nothing to do with food or water. He did have a small bowel movement and i saw him urinate a few times. So, now imREALLY scared. I took him to the vet hospital for another emergency visit and they ran a ton of tests & x-rays. Everything seemed normal, but his WBC was high and theythought his glucose was a little higher than normal due to being so anxious and having increased adrenaline levels. They also found in his x-rays, that his intestines were filled with gas and also suspected the slight cough he had to be pnemonia or a sign of it. Tommy has thrown up a ton in his lifetime, and i always thought this was cause he ate SO FAST. Most vets made it seem like it wasn't a big deal. I am so scared, I love this cat with all of my heart & soul. He seems alert &basically happy right now, he is constantly purring and relaxing. It's been almost 6 days since he has aten food on his own & water. The vets gave him fluids through the skin and he will eat a LITTLE bit of his dry food when hand fed. He also has eaten some catnip in the last two days and licked some cat food gravy. But that's about it. The vet gave me two different antibiotics, not sure the name caus ei'm not near the medicine now. He has such a hard time accepting medicine and gets so worked up taking it, even in fluid form. Please Help me.... The vet said other than this, Tommy is very healthy. This seemed to happen so suddenly and it's driving me nuts. He does seem to release gas from time to time, especially after some catnip, which he eats. What's really driving me cray, is he still seems so happy and calm AND LOVABLE like always. What can I do?
Answer:
 If he is congested at all, that would prevent him from smelling his food & cats have to smell what they are eating. You weren't feeding any of the recalled foods have you? You can get nutrastat at the pet store which will get some needed calories into him. Try heating some chicken broth (barely warm) & put it on his food.
Answer:
 Thank you so much for replying. He definitely didn't eat any of the recalled food, but i still wonder if some snuck through into other non-listed brands. That was the first thing i thought of. I will definitely use the recomendations you gave What is nutrastat? Thanks again for the help