I ended up in #AutisticOverwhelm today at my company's employee conference.
From the start, I was stressed by the volume of people, and the loudness of the hubbub they were making. Queued for 10 minutes for the supplied breakfast, only to find that I didn't like the look of the #vegan option. Decided to go and look at the stalls as it looked quieter in the hall, but it was getting increasingly louder, and I was getting increasingly dissociated. Workmates found me and said hello, but I couldn't hear them well enough to have a conversation. I retired to the chill-out area, to try to clear my head, and some guys came in and sat near me and one of them started playing loud techno on his phone, causing me to snap at him to turn it off. Eventually it was time to go into the "lecture theatre" for the intro speech. It was too packed, and I was already feeling anxious so I didn't really feel able to sit in a throng of strangers, so I found a quieter corner at the back, by the raised seating, to lurk. Loud music and lightshow. CEO came onstage, did smalltalk and intro, then started pumping the audience to chant and shout. I was already thinking I needed to leave. Then he told the people in the raised seating to start stomping and yelling. That was it - I literally ran out of the theatre, and crumpled, dazed, on some stairs in the corridor outside.
Lots of days I feel the impostor syndrome. I "cope well" with work, especially working from home.
Today I am more aware than ever that I'm #ActuallyAutistic
One of the management came out to check on me soon after. I'm glad he waited a few minutes, because I struggled to speak. He was understanding and nice about it. I explained I'm Autistic, got overwhelmed (and I don't think I was very polite). He told me where I could go to chill out, and came to check on me a short while later. About 45 minutes later, he came to see me again, and after realising I was still in shutdown, told me I should go home.
I got my wife to pick me up - fortunately she could fit it round her schedule with some imagination. I worked from home all afternoon, with emails flying in about what had happened, and my manager checking I was OK too. I took on some less taxing work, as my head was still frazzled and I felt like I'd lost about 20 IQ points. That kind of stuff calms me - I guess it's a bit of a #stim .
Not going to be going to one of those again, that's for sure.
Do you tend to stim with clicking your mouse on whitespace when you're bored? 
Link: 
but possibly a 
I eventually calmed down. 