I have no idea, but hope Jackson feels better soon.
Def call the vet and see what they say.
Not to scare you, but after Scrappy had surgery for what we thought was an absessed tooth, he was wheezing and breathing really hard, also not eating but drinking tons of water. He ended up getting really bad seizures and eventually passed from them.
I'm sure whatever is ailing Jackson is nothing like that, but just reminded me of him and how scary and sad it was to hear him like that and not be able to do anything.