@goosetuffs - I don’t have anything to add to Joanne’s and Rosemary’s posts except to tell you not to give up.
I have both the history of diarrhea and pain and nowadays constipation.
After local GI gave up on me I went to Mayo, Jacksonville. I kept going until I got a diagnosis and plan for treatment. Even at Mayo I had the feeling they got tired of seeing me! I’m glad I kept going because finally there was new medical information that applied to my problem.