Maybe you should try a CT enterography or MR enterography or an intestinal ultrasound (I've had an abdominal ultrasound before but intestinal ultrasound is more specialized than abdominal ultrasound and not just anyone has the expertise to do intestinal ultrasound properly). They can pick up on some different things that other kinds of imaging aren't designed to show. And if you complain loud enough you absolutely may be able to get a colonoscopy and/or endoscopy. I just had them and I'm 22. Whatever you do, PLEASE, please don't give up until you find an answer! 2 years ago I also noticed a lump in my abdomen, though in a different place than where yours is, that my PCP's nurse practitioner thought might be a hernia. He and I could feel the lump, but several other providers felt my abdomen and couldn't feel a thing. One GI did feel the area and feel something hard but thought it was my SPINE! I had Xrays, abdominal ultrasound, and MRI, that all showed nothing, and so I finally gave up. The lump didn't go away and I developed worsening diarrhea and other symptoms, and so this year I finally went to see another GI. He ordered a CT enterography that showed Crohn's in the area where the lump is, and then I got scoped to finalize the diagnosis and am now on meds to get this safely into remission. I'm blessed to have a type of Crohn's that is more reversible than most; otherwise those 2 years that I spent giving up on finding an answer could have had more consequences. Not trying to worry you or anything, I'm just saying don't be afraid to be aggressive in advocating for yourself and don't let anything discourage you from getting to the bottom of your symptoms. You deserve answers! Keep us posted if you want to. You got this, girl!