I am not an expert or anything but I am really amazed at how much progress she has made. I remember the earlier post about tossing the chair and how ahead she was academically. I was thinking she was going to end up in that school you didn't want her in for sure.
I understand how rotten it is to be the parent of the screaming kid. I have been there many times. On the plus side, it seems like a good meltdown if there is such a thing.
First, she is thinking clearly even while melting down.
My kid has had meltdowns where he seems like he is completely not really there anymore.
She is acknowledging behavior norms "people are happy when they dance". She is stating that the feeling she is experiencing is beyond her control "I can't calm down". And she is concerned about others' perception of her and how they will feel "everyone will worry about me"

My son was on stage with his drama club for the first time at five. At the practice following the program I heard the teacher asking the kids how they felt on stage. Most said it was cool or fun. My son said "It freaked me out. My face felt hot and my heart started beating fast. I wanted to run away and hide but then I knew people would be angry or laugh at me so I just waited for the music and when it did I just started going through the routine."

I just mention this because the situation might trigger anxiety in any kid so if that is already an issue - well, yeah what happened.

I don't mean to sound dismissive or anything like that. I have just had a heck of a week with DS and doctors (see connective tissue thread). It has me thinking of how hard it must be to BE a 2e kid.

I hope your family has a nice weekend.