Just this past Saturday I had a meltdown.
One of my new habits is to spend Saturdays sitting in a Barnes & Noble cafe with my netbook writing extensively in my journal. On this particular Saturday, I stopped to call a friend to find out when they would be home as I would be stopping by later. While on the phone, having a very NTish conversation, she remarked about a baby crying in the background.
I froze.
All of a sudden, the barriers I had erected in my head allowing me to function in society all came crashing down at once. Every little sound, from the baby to keyboard clicking, coffee machine humming, every person talking, the cash registers, EVERYTHING... came crashing into my head at once.
I shut down.
My phone conversation went from extensive talking to quiet, one or two word answers. I pulled myself deeper into my own mind to block out the world that was rampaging all around me.
I felt tiny. Very, very, very tiny. I felt like I had shrunk and the world had suddenly grown to monstrous proportions, ready to stamp out my existence with a mere flick of the wrist.
It took the better part of 10 minutes before I could compose myself. I actually ended up staying there for nearly an hour longer, as once I was able to re-erect the barriers, I was once again "fine" in the sense that I could function somewhat normally.
A meltdown to me is different from a panic attack in that I know exactly what is going on, what is about to happen, and can watch it in my head almost dispassionately. It is like that one part of my brain disconnects from the rest of my psyche, letting it do it's own self-sustaining things while it goes out for a smoke. In the end, I'm usually able to regain control and not make a complete and total public ass of myself in the process. USUALLY.