For a while I've had issues with eating enough.
I feel uncomfortably full after a normal sized meal or large shake. This brings on nausea to the point I have to puke right after a meal.

I've always thought this was PED related.
Today I had a large high calorie shake and felt the urge. I was doing a search and found
" pyloric valve spasm"

Some have pains and heartburn. Others simply feel full and nauseated till they puke.
I've not been diagnosed with this but I found a video on YouTube for "pyloric valve release"
I can't post the link but a doc is using a small dumbell for it. I did this standing up with my fist.
Surprisingly my symptoms of nausea and fullness went away. I've never felt hungry after a big shake. After this, it feels like I never ingested anything.

To properly diagnose, one needs a thermal imaging or better yet endoscopy. I've heard of surgery but I've also heard of botox.

Just something to think about if you're having similar issues.