As mentioned by another poster, waking up in the middle of the night is not a 'normal' symptom of IBS. It's imperative that you have GI tests to rule out any IBD. Microscopic Colitis, possible gluten intoleranc(celiac or silent celiac disease) are also a possibility that testing could rule out for you.
I remember at it's worse, there were a few times that I awoke during the night for whatever reason, but as soon as my 'mind' was awake, my intestines ALSO woke up just as fast and I had to make a run for it. But my bowels, themselves, were not the reason I woke up.
A colonoscopy with several random. spots biopsied could help you rule out a whole range of conditions.
Might not sound like fun, but possibly finding the cause of your symptoms, being treat accordingly, and living with less bowel problems probably sound pretty good right about now, huh?