You sigh when you look at your clinic appointments for the day. You have been seeing a 29 year old woman for several years, and she always has the same chief complaints. You haven't been able to figure out the diagnosis despite a battery of tests. She always has headache, belly pain, back pain, and chest pain. Her headache is not characteristic of migraine or cluster; it responds a little to acetaminophen. She has had a negative CT abdomen/pelvis, no response to a PPI, and a negative upper endoscopy. You initially held out on back films but finally caved in, and of course, they are negative. She's had a negative EKG, CXR, and stress echo. She also complains of nausea, bloating, irregular menses, difficulty swallowing, and a "lump in her throat." These symptoms are interfering with her work, which she really likes. She has no odd animal, occupational, or environmental exposures. She only takes acetaminophen at recommended doses. She does not drink, smoke, or use any drugs (which you have confirmed with a urine toxicology). She hates coming to the doctor, but simply wants to get well.
Challenge: This constellation suggests what diagnosis?