Is a 24h fast long enough to have problems with refeed?

I did a 24 dry fast three days ago and broke with regular food. My stomach hasn’t been right ever since.

Discomfort after just 24 hours seems a little odd, and may just be the volume or the specific foods you ate. How are you defining “regular food”.
It may just be too much carbs or fat too soon, but 24 hours was not enough time to kill off your microbiome.
I agree with Dunning who says don’t worry about refeeding on any DF up to 3 days, but I’ll check to see what Yannick says and try to respond better. I would say try again and start with a cucumber then other veggies and easy proteins and fats like eggs and avocado before a steak and pasta.

Hope that helps.