Colonoscopy/sigmoidoscopy side effects

since having a colonoscopy, polyp removed, and then a follow up sigmoidoscopy 10 months later, residual stem removed, i have had some problems. after the sig., eight weeks ago, i have had heart palpitations. never had them before this. my internist said it was probably a result of the prep throwing off my electrolytes and prescribed magnesium. that didnt work and now i have to see a cardiologist. this week i started experiencing lower left abdominal pains, went to the ER, had a catscan, and was dignosed with diverticulitis and am now on heavy duty antibiotics. when the stem was removed eight weeks ago, the doc spent about 20 minutes trying to fish out the removed stem for biopsy. could this outbreak of diverticulitis have in some way been caused by the sig.? a good freind thinks that his colonoscopy, four years ago, permanently changed his bm habits. Does anyone have any ideas or info about these procedures causing these or any other longer term effects? Thanks. rack