Tenderness and pain on lower right side of my stomach?

About me: I am a computer professional, male, 35 yrs old, married with three kids.

I am having this mild pain on lower right side of my stomach (just above hip-bone). When I lay-down on my back putting little-bit pressure on the area with my fingers hurts otherwise it is bearable.

Saw my doctor of internal medicine having 20+ yrs of exp. He did physical exam checking for appendices, hernia, and ruled out both. He then did urine test, blood tests, ultra-sound and CT-Scan because he was thinking it might be gallbladder and said everything was fine and finally said I am sorry I don't have a solution; please see gastroenterologist.

Does anyone know what it is? I have mild anxiety disorders and little bit depression for a long time that I am living with w/o any medication.

Thanks!

He said see gastroenterologist, good advice, You know there is such a thing as referred pain, pain from one organ, referring itself to another organ. I had an ulcer that hurt in the back, went to 8 doctors and they could find nothing, finally it perforated and the contents of my stomach dumped into the peritoneum, (abdominal cavity) I had immediate surgery, but almost died from peritonitis. Pain is always a warning. Follow his advice. It may sound strange, but the vagus nerve connects to the stomach and spinal cord, and can send pain signals to any number of places, including your right lower side.
You are so fortunate to have a Doctor of Internal medicine who will admit to not having a solution, most will just give you a nerve pill. Hang on to him, he's worth his weight in gold. Why not ask him to refer you to a gastroenterologist. I am sure he knows a good one, who will not just start running Endoscopy tests, but will test for the H. Pyloric Germ which is responsible for ulcers , before he runs any other tests.

You need a holiday, preferably one with plenty of relaxing physical activity.
Maybe you are bouncing your kids on your knee, and that's causing muscle strain?