Over the last couple of years, I have had a sharp pain in my back the right side of my spine. It is located in the middle rib area, no where close to the spine. Previously, it only appeared when I was standing for several hours and would go away when I sat down. Now, it has become constant when I stand or sit for 5 minutes and has always been in the same spot. It will go away immediately when I lay down. I have good posture and in decent shape at 36 years old. Any suggestions on what could be the issue?