Your adrenal, or suprarenal, glands are located near the top of each kidney. The kidney are located on the back plane of the body, just above the hips. In this case, if you're having abdominal pain, I would think that the pain is NOT being caused by the tumor.
Have you gotten your gallbladder area examined since the removal? The
gallbaldder sits in the top right corner of your torso...you might want to get an ultrasound or other diagnostic test to check out what's going on.