What is a natural way to treat widespread chronic pain?

My doctors have no idea what might be causing my pain, but I have spent the last 3 yrs with chronic pain in my neck, shoulder, entire back, and currently my hips. I have problems standing for long periods of time because it cause my feet to hurt as well. After taking 27 pills a day and several rounds of physical therapy, the pain is still there with no clear idea why. I've tried stretching, heat, and ice as well. I'm only 22 and used to live a very active life, but due to the pain I can't do most of the things that I love. Does anyone have an suggestions how to help ease the pain?