Sudden Tolerance loss?!

Hey all, kinda worried about this so asking if anyone else has had similar experiences.

Have you ever just had your tolerance disappear? It seems to happen to me with stress.

I had exams just over a year ago, and the stress got pretty severe – I stopped sleeping, had issues breathing for about a month, whatever. But it took me several months to be able to stomach a pint again.

After awhile everything went back to normal, nights out at the pub? Totally fine. I could pack 5 pints into a night again and have no issues.

But recently I played a drinking game at a party, got totally ruined, and it’s happened again – one drink and I feel dizzy and sick the day after.

Is this normal??? Is there a reasonable explanation? Had anyone had a similar issue? 😅

Cheers for any other perspectives