hey i don't know if you're still following this thread but i wanted you to know i am going through something very similar.
had a meltdown a few weeks ago which mas made many of my nervous system habits much more exagerated and obvious.
including how irritable and shaky i get after sex, or ogasm, including the tight throat.
i believe that for some deeper reason, my body is going into fight or flight mode after ogasm. this is possibly linked to the shame associated with ogasm but i intend to work on this with my therapist, wife and friends.
in the meantime i think i will take a beta blocker after any ogasm as this blocks adrenaline and allows my body to keep calm.
would love to know if you have figured anything out yet..