I take 50mg for (recovering from) back surgery pain. It quiets the areas of the brain that are now "switched on" from years of chronic back pain. 3-4 months on it and these symptoms hit me (female, 50, fit, avg height). Thought I was having a heart attack because of the jaw pain. Went to ER and did an overnight. All tests say I'm healthy. Really the only thing different is the nortriptyline. Has anyone experienced any of these symptoms?