I had some nightmares on Gliclazide (actual nightmares not metaphorical ones) and felt a wee bit woozy initially but never had that kind of stomach pain. I would definitely raise it with your doctor; it may well, of course, be something else altogether...and bugs do increase BG. By the way, I got my blood sugars down far more easily an in a far more controlled way when I came off Gliclazide and went low carb. There is always, I would say, an increased risk of hypo on Gliclazide if you are on certain diets. Anyway, I hope it resolves itself soon...maybe just an initial reaction which will ease. Anything else changed?