There's other things in those products that could have caused your symptoms. I think it's too soon to blame the sucralose. Sucralose is real sugar with a couple of extra atoms attached (can't remember specifics) that make it indegestible. Still sugar though, which is why it tastes real. Supposedly this stuff is kinda neutral as far as your bodies chemistry goes?
Anyway the chocolate bars have fat replacements that could do it, and lots of sugar-alcohols (although your might not with the sucralose). Haven't heard of sugar-alcohol causing that problem, but it's still something "un-natural" that could be blamed. I'm sure the gummy bears have similar things that you don't normally ingest. 'Sides a whole bag???
Sounds like me.
Have you tried just trying something else with it? Diet Rite cola uses Splenda. Might be a good way to try it without introducing other wierd stuff.