I experienced this early on when my TOS was at its worst. Getting my first rib adjusted by a chiro (or mobilized by a PT) helped dial down all my symptoms including this one.

Another potential help is what I call "muscle relaxation meditation". You can search the forums for details.

Another potential help is diazepam to calm down the nerves and reduce muscle tone.

But yes, I've been there and others on these forums have as well.

HTH