I feel like there is electricity on my skin. I have visuals of flashing in my mind's eye like lots of christmas lights. My hearing "throbs". My muscles tense and I clench my fists. Everything becomes super irritating. Sometimes I hit myself and other times I completely dissociate and can't move, staring into nothing. I often have a hard time responding to people. If I am in public I need to escape immediately. Sometimes I run away. Sometimes I start walking until I am exhausted.

I just internalize my meltdowns for the most part.

Is it healthy? No, but it was worked for me this far.

Difficulty speaking, severe tension running through my shoulders, neck, and jaw. Fist clenching. A lot of rocking with some spastic shaking. Very similar to what you've described, save for the sweating.

Sometimes, I'm actually able to dissociate myself from them, so I can sit there and mentally call play-by-play while my body remains locked up and over-stimulated. That's a bit of a wild ride.

I basically just become mute and summon an uber to go home. In my head, the windows XP shutdown sound plays.

Loud screaming and crying. Fist pounding on the table. Lots more crying.

How old are you?

I too am in the process of getting a diagnosis. As for my meltdowns, I have two phases: Muting myself, or cussing everyone out loud, while I try to internalize the feeling of crying.