Try to avoid overally acidic foods (oranges, grapefruit, etc) and eat small/frequent meals. I also have issues with ulcers (I have a lot of stomach issues) and have to follow a strict diet and eat at certain times. You can ask your doctor if you're able to take antacids too which can help the issues.
Sweat* and the Dexilants generic name here in Canada is Dexlansoprazole.
My diet is pretty healthy, I avoid coffee, was a heavy chocolate eater until all these symptoms arose at what point I quit, I stick to lean chicken breast, fish, lots of fruits and vegetables and only drink water and on occasion a Gatorade if I swear too much so my diet is pretty healthy now without the extensive amounts of chocolate haha!
It's very possible, especially if food helps the nausea for awhile. You could also have gastritis - it causes a burning pain in your abdomen, nausea/vomiting and a very full feeling after just a few bites of food. PPI's work to decrease the amount of acid your body produces, and usually help within a week or so - if taken as directed. I've not personally heard of the type you're on, but they all work in similar ways. What kind of food diet do you follow?
It's clear alcohol makes your issue worse, so I would strongly suggest avoiding it. It'll help your stomach heal, not to mention help keep from getting more.