I have the same thing, IBS-D and i also feel nauseous and dizzy sometimes. I don’t actually throw usually, maybe once a year. I have been in “remission” but ever since I had COVID a couple months ago. It’s back. My doctor put me on a medication called Dicyclomine and it helped the IBS pain but it made me very nauseous and actually throwing up more often than without taking the medication. I always try to find triggers and avoid them as much as possible. I have a list of triggers in my phone to keep track. Sorry I’m not much help but I relate to you.