I know I've said this to you before, but I'm still thinking it's neurological because it sounds pretty similar to the simple partial/autonomic seizures my husband has.
When it happens, he simultaneously feels like he's going to pass out, lose his bowels and vomit. He breaks out in a cold sweat, his heart pounds and he generally feels disoriented. He is aware of everything around him and he can talk, but he usually has to lie down because he feels so wobbly. He usually feels very tired afterwards. Sometimes he's had tingling in his arms. He has only lost consciousness once -- unfortunately he was driving when that happened.
Over a period of several years he underwent Holter monitoring, cardio stress testing, tilt-table testing, EKG, got checked for inner ear problems, and was even rx'd medications for anxiety, thinking these were panic attacks. All his neurological signs were normal. And an EEG at the hospital was inconclusive. A brain MRI that the first neuro read did not show anything. HOWEVER, when we had an epilepsy neuro read the same film a couple years later, he FOUND a very small abnormality present in that image and a subsequent image revealed a rapidly changing vascular abnormality in the right temporal lobe (thus the simple partials seizures).
Not saying that this is necessarily what's going on with you (the abnormality part) but I really do think there is a possibility that this is a temporal lobe issue.
I hope you can get in to see a neuro soon -- I know how frustrating it is to have something like this going on and not have any answers from the "experts." If they can't get you in for 6 weeks, make it your mission to call them EVERY. DAY. and ask if they've had a cancellation. BE the squeaky wheel even if it means you end up on a first-name basis with the appointment desk and they start to know you by the sound of your voice! I've done this and it can work. They will fit you in, one way or another.