can it be acid reflux, if you get the pain in your arms? lol.. it doesn't feel muscular to me either, someone said vein, which is exactly what I told my husband last night in the midst of it all, like its clamping off the vascular system for a short time due to extreme pressure from the heaving, and yea, it hurts BAD!!  if I can do it with as little sound as possible, it doesn't seem to hurt my throat as much, go with the flow, so to speak, try not to fight it once it's inevitable, tho' at times it can't be helped.. I've had some typical chest & stomach pain and once really bad in my low back.. got nods of sympathy from P/A @ Drs office, but no answers... I'm reasonably sure it's the pressure on certain parts of the body, wretching and heaving, generally with little output.. I take a lot of Phenergan to prevent the vomiting, being as it's a side effect of some meds I take & not a flu, I prevent it if I can, but like yesterday it doesn't always get me there.. I've found that a heating pad helps the arm pain some..