I have pain in my wrists, fingers, knees, and back. X-ray shows no Arthritis, what could it be?

I have had physical pain for at least 5 years now. I was in an abusive relationship at one time, so I figured it was injuries from this. I have recently told my doctor about these symptoms. She checked for Arthritis by blood testing and x-rays-found nothing. In my hands and wrists, it is often shooting pain, and throbbing, they other ares of my body are aches and pains. I am only 27, what gives?