side tenderness/lump at waist level

I have off-and-on tenderness of the bilateral sides, at about waist level.  If I press on the area, it is painful and there is a lump.  The pain is dull/achy and the right side is usually worse than the left.  Any idea what this could be?

[Paderla Anitha, DNB]

Hello and hope you are doing well.

If there is tenderness when touched, then it could be due to trauma or a superficial infection of the skin. The other causes could be gastritis, peptic ulcer disease and GERD. Disorders of the colon could also cause pain. Kidney disorders too produce colicky and sharp pain. Sometimes anxiety with flatulence can cause this pain. You will need to consult your primary care physician for proper evaluation of pain and therapy.

Hope this helped and do keep us posted.