i have a 6 year old himalayan cat that has stopped eating, he has been salivating some,too. he just lays around and barely moves. a day or so ago he was sneezing some and now he cant hardly even meow. he has aslo been dry heaving a little. he occasionally has a hairball problem but this isnt that kind of behavior and i gave him his hairball medicine a few days ago. what could possibly be wrong with him?