My mother and I both got stevia poisoning after a good year. We were consuming so much each day that it just became toxic in our bodies.
I looked long and hard online to find one little article about other people experiencing the same thing.
We just kind of always assumed that since it was "healthy", it was ok to have as much as we wanted. Too much of a good thing = not good .
So trust your gut (haha...no pun intended). You know that it's the stevia that you're reacting to. Just because everyone else in the USA thinks it's the second coming doesn't mean you're not reacting to it! (And to Stevia lovers - I'm not knocking it. It's great in moderation).
I started using xylitol, which is infamous for the same symptoms: bloating, stomach issues, diarrhea even. But many people get used to xylitol with continued use. When I first started using it, I bloated a bit, but I don't experience any side affects from it anymore!
So if you want to take the risk (if you're not allergic), try to continue the stevia for a few days and see if it gets better. If not, there are other substitutes out there - lo han guo, xylitol, eyrithol (sp? I'm too lazy to look that up haha).