I had something similar, but instead it was feeling full and nauseous with just a few bites. Food smells were the worst, and can still trigger nausea for me. I never really got around to figuring out the cause because I was bad at getting healthcare for myself. But it cleared up, weirdly, around the time I had my wisdom teeth taken out. I got my life back after that, and I hope you do too very soon.
Wishing you the best and hope you get some answers with your upcoming visit.