Hi, I Have Had 2 Back Surgeries In The Past

Hi, I have had 2 back surgeries in the past for lower herniated discs. I also have stenosis, but lately, for the past 9 months, I have been experiencing severe pain in my lower back, buttocks, sides and backs of my legs, thighs and calves. This is so debilitating that most mornings I am unable to walk without pain or to stand erect for any length of time. It feels like all my tendons are shortened and pulled. My bones hurt too in my lower back and pelvis. It feels like I have 2 screwdrivers jammed into each buttock. My GP prescribed 800mg of ibuprophen 3X a day as needed. I take this as a last resort because it has begun to irritate my stomach and I have pain when I eat food. I don't know what is going on with my back and I don't know which kind of specialist I should see. Can you tell me which kind of doctor I should make an appointment with to address this pain problem? Thank you, Maria Brigham