What Causes Pain And Contractions Throughout Neck And Back?

I am experiencing odd muscle pain/contractions throughout my neck and upper back and have pain in my hips. A recent x-ray shows osteophytes forming on my C5/C6 vertebre and mild sclerosis of the head of both acetabulum. I was injured last year on my hip when I fell on a slippery rock. I also had a minor car accident 20 years ago (hit from behind). I can no longer sleep on either side due to the pain. Walking on flat surfaces is ok, but stairs/hills is painful. I m 46 years old and never had problems before this last year. Why is my body creating these ostephytes now and why am I experiencing odd muscle contractions and pain in my neck and shoulders? My left side is worse. Thank you.