the usual medical gaslighting, nauseous randomly throughout the day?

Hi, short version in the title, basically.

Since December, I’ve had a strange nausea reflex that seems to originate from my stomach area. It happens right in the morning after waking up and then randomly throughout the day—mostly when I exert myself physically. The weird thing is: I had the exact same issue two years ago. Then I caught something (the doctor suspected norovirus), vomited for a full eight hours—and after that, it was completely gone. Until now, in December.

So far, I’ve had a gastroscopy, which showed mild gastritis. Interestingly, this was despite taking 40 mg of pantoprazole in the morning and evening for three weeks before the exam.

My question is: What else could be causing this? Of course, psychosomatic causes are a possibility, but since it happens even in completely relaxed situations and for whatever reasons doctors these days just seem to dismiss you after checking only 1 little thing...

Just to describe how it happens: I feel pressure in my stomach area, and if I press on it, it hurts and seems to trigger the nausea faster. Then I go through 5-6 gag reflexes, and if I’m unlucky, stomach acid or whatever I last ate comes up.

I’m, of course, seeing my general practitioner again. He just gave me another bottle of pantoprazole, and dismissed my "could this be my pancreas?" with a no. At least we'll finally take some blood next in two weeks but I don't know what exactly he's checking because he obviously didn't explain anything..

I’m also not pregnant, I don’t have any other illnesses, and I’ve been on SSRIs for 13 years—currently Escitalopram.

So my question is: Has anyone here experienced something similar? What else could be causing this? Could my gallbladder be a possible culprit? I don’t have any colic or anything like that, though.

:( Sorry for the long text wall—just hoping someone can point me in the right direction. Maybe one of you even had the same stuff happen