My cat just turned 17 years old. He used to be around 16-17 pounds. Now he is maybe 6-7 pounds. He is super hungry and eats a lot of canned food but continues to lose weight. He is not diabetic. He throws up clear liquid every night during the night. A few weeks ago, he had an intestinal blockage which passed after a few hours of panic and pain. His breath is horrible and he has a lot of nasty gas. He will stroke out if I try to take him to the vet - super shy and doesn't like other people. Any suggestions or thoughts?