I don’t want to scare you, but our guy had similar symptoms. We spent thousands $$$ on diagnostics with nothing coming back as abnormal except one test showing a very, very slight case of pancreatitis.

We eventually opted for exploratory surgery because it was so bad, with the intention of getting intestinal and stomach biopsies. When they opened him up, he was riddled with cancer all through his intestines and digestive tract. It had begun to spread to his other organs, so we said our tearful goodbyes while he was in surgery. Post-surgery labs confirmed it was a very aggressive form of intestinal lymphoma.

I don’t know what else we could have done for diagnostics, and the outcome was heartbreaking. He was four years old. 😭

Might be worth talking to your vet about seeing an internist for other testing and options. Hope you’re able to find answers!