Jan, are you on a probiotic after all your medical issues? You must have been given antibiotics. Your tummy may need some enzymes or hydrocloric acid after all it's been through.
If you're looking at joint pain, the RA restriction on nightshades is worth a try. I gave up potatoes, tomatoes, peppers and eggplant a year ago. It takes 90 days before you can reintroduce them for testing. I waited 6 months - tomatoes were terrible - instant pain and inflammation. Potatoes were inconclusive - I need to try them again. Haven't tried the peppers yet. It was tough during our harvest season, but it's been worthwhile for me.
Good for you on using a misadventure to improve your health. I would have returned to eating everything in sight. I allow myself 4 dark chocolates a day, but on too many days more slid in. Let's work on this together.