Ncef, is your mom celiac? You mentioned an intolerance to wheat. To me, that means celiac disease. And if she's also unable to tolerate dairy could means she's celiac with a cross-reactivity to casein the major protein in dairy.
If your mother is celiac, you should be tested for the problem. It's an autoimmune disease that runs in families. It may or may not show up at birth. But these days, more and more adults are finding out they're 'silent celiac.'
If you've got an actual lump, it could suggest a hernia. Get it checked out.
Hmmmm... again (as I seem to state in all my posts so far LOL) check with a doctor. If there is a history of GI problems in your family you may become more suseptable than most people to problems. You might was to be checked for hernias, tumors (because of the lumps), gallstones, bacterial overgrowth in the small intestines, and maybe throw in allergy tests for every food allergy known to mankind! LOL It is possible to develop an allergy to something you previously didn't have a problem with. I do wish you the best and KIT if you like!