Thought "there is something wrong with me"

My whole life I’ve had tummy troubles, some IBS, done so many different tests and food changes trying to pinpoint what triggers me and what doesn’t. My tests always come back showing there is nothing wrong with me, I don’t have any diagnoses, I’m seemingly healthy. I don’t struggle with weight or anything like that and I eat very healthy foods and have for the last decade… but I’m still struggling with tummy issues. Stomach aches most days and I can’t pinpoint a particular food (I’ll eat the same thing another time with no problems). I don’t feel good about 80% of the time so my thought is “there is something wrong with me” but I cannot figure out what it is! It affects my quality of life, my sleep patterns, my relationships… When I think this thought sometimes I feel frustrated and just want to cry and throw my hands up and other times I feel determined so I try and do all the things like keep a food journal and try this and try that but nothing ever changes and I’m not finding the root cause of whatever is going on… I just want to feel better physically. And I realize saying “I don’t feel good 80% of the time” is also a thought… saying “I don’t feel good” is also a thought… I’m comparing how I feel when I don’t feel good to how I feel when I think I DO feel good… which is no stomach pain. I guess maybe I’m just trying to figure out how to think differently about this if the pain/stomach issues never change.