I had been in pretty high spirits. The class had contained some interesting material that forced me to think in new ways. Consequently, I had a lot of energy to work off, and had been flapping my hands and walking so fast I was at times actually running. I was quite happy, but also in a state of high "alert".
As I stood on the grassy swatch of ground next to a busy road, waiting to cross, some idiot decided it was a good idea to honk at me.
A car horn is supposed to be used for its intended purpose: Namely, to inform another driver that if they continue on the course they are going, they are going to run into you.
A car horn is not a greeting. It is not a casual communication device. It is not meant to be an insult or a substitute for the profanity of your choice. It should not be used to say, "I shall now be a massively boorish specimen of humanity and use ear-splitting noise to declare this random stranger at the side of the road to be someone with whom I would agree to copulate."
If you are autistic, a car horn--especially when you are not protected by a car of your own--is definitely not something you want to expose yourself to.
About half a second after I felt something like a tent peg going through my skull (without the explicit pain, but with the same kind of intensity), I realized I was sitting down on the ground, slumped forward, and that my throat hurt from screaming. I was also crying uncontrollably.
I had to sit there for a further five minutes, trying to collect myself to the point that it would be safe to cross the road and duck relievedly into my apartment. It took me another half hour to realize I had also bruised my leg, by which time a tension headache had made itself an unwelcome guest.
So remember: Do not honk at random people you find on the side of the street. They may be autistic, and you may ruin their day.
Thank you for your time, and back to your regularly scheduled programming....