Many of your posts sound soooo familiar. I've been through similar symptoms for almost 20 years. Diagnosed as having several problems: ESOPHAGEAL SPASMS, PARTIAL INTERMITTENT BOWEL OBSTRUCTION, GERD, ADHESIONS
First was the esophageal spasms--felt like a labor pain or contraction. Waves of pain from just below my collarbone down nearly to my waist. Probably stress-related, as I had only had heartburn occasionally before that. Nitroglycerine was prescribed for that. I didn't notice anyone else mentioning nitro--maybe it's no longer used for that. It worked, but brought on a headache, but at least I could sleep.
A few years after an ruptured ectopic pregnancy (also hysterectomy and surgery for endometriosis) I began to have the same type of pain but this time between my waist and navel. Without treatment, an episode progressed to violent vomiting and trip to the ER. X-ray showed small bowel obstruction (partial). Treatment was pain med, a few hours sleep and observation until the obstruction resolved on its own. Rx for vicodin allows me to do this on my own. Bethanechol in small doses can also help if I'm going to sleep. It increases GI motility, so is only used if the obstruction is known to be partial. WebMD has a good explanation with illustrations.
So by history, adhesions are assumed. (Now I'm considering surgery for those, by a gynecologist who specializes in laparoscopic excision of endometriosis.)
Lifestyle management includes the usual recommendations by gastroenterologist, and further explanation of the usual "fiber-rich diet" rule: be careful about the amount and type of fiber: No fiber additives; limited amounts of very dense fibery foods, etc. (He said he had a patient with similar symptoms who thought she wouldn't make it back from a climbing trip--symptoms brought on by eating "Gorp".) I've had the problem brought on by too much of a favorite very dense multigrain bread.
GERD also became a problem after the bowel obstruction episodes started. Basically, if my gut is full, I wear tight clothes, bend over or squat, reflux happens.
Hope this helps some of you, as your comments have helped me.