Oh my gosh, I'm so sorry you're going thru all of this and that those doctors have been so invalidating!!! I know that feeling of everything coming back normal.
I'm also experiencing the internal shaking that's relieved by gas/bowel movements and am wondering if it's MS/Young-Onset Parkinsons (I posted a similar query here which got some helpful responses: https://connect.mayoclinic.org/discussion/finger-twitching/). I haven't exactly experienced your other symptoms but similar--parasthesia in my arms when lying down, muscle twitching, feeling of something stuck in my throat. The internal shaking is the main thing. I'm curious about the stuck-in-throat feeling and the possibility that it might be linked since you're experiencing it too.
I'm seeing a neurologist in a month and getting an MRI tomorrow and will update you as soon as I can.

I'm NOT a doctor but I've read that Vitamin B-12 deficiency exhibits similar symptoms and was thinking of getting tested for that. Just tossing that idea out there. Hope you find some relief with the gynecologist