I AM LOOKING UP RE IBS. Don't Know If I

i AM LOOKING UP RE IBS. Don't know if I have it or not. I go from constipation to runny watery bowels. I am 90 and my Dr. thinks I should have a colonoscopy. She suggested I see a Dr. to see if I should have one or not. I think I am too old for this. I have had congestive heart failure in July & was in hospital & rehab. Should I just live with it? I can function pretty much - have't found any food yet that causes it. I live alone and still driving so I am doing pretty good. I am widowed.