I previously got this symptom too and the doc diagnose it as gas
poisoning.
Cos i was painting the windows grills with some paint that
contains gloss. And i inhale too much of the smell of the
paint.
Anything i eat or drink, i will vomit. Even if plain water, i
vomit immediately.
I was given a jab on my butt and even after this jab, it took me
another week to fully recover.
TS, pls go see a doc...