I have had 5 back operations ,I,m now left with a lot of chronic pain .i was put on 20mg of on on & up to 4 oxymoron a day when required for pain, & amatriplene at bed time, I now have been told because I have been on these for a few years I should come off the oxynorm first because it s causes more pains then get off OxyContin , they also put me on noritriplene. I now cannot sleep at all at night I take 75mg of noritriplene I get a lot of pain in my lower leg it stings when I touch my leg & I am totally confused .help