I wouldn’t force feed without vet guidance. I would, however, call your regular vet and have a serious conversation about what you can do for her, and what sort of prognosis your vet can give you.
I will say she needs to start eating, so I would get her in to your vet today if at all possible.
I’m so sorry this is happening. It’s scary when it’s so sudden. My heart goes out to you as my stinky kidney cat burps in my face. Let us know what happens?
Yellow vomit is bile, and is something we see in Dobermans when they have an empty stomach for too long. When was his last meal? What happens if you give something small, like a little plain yogurt?
Agree with Laura-
I would definitely watch him closely. If hole gets any worse, probably call the vet. Meantime, if he is getting an appetite, I would keep it bland. Boiled rice and chicken…. hopefully he is fine????????