That sounds like a scary incident for you...
They have these cards in the UK for exactly this kind of scenario, in which people in a position of authority, who could make life very difficult for you if they don't understand where your behavior is coming from, can be shown that you do have an officially diagnosed condition, your extreme reactions might be out of your control at that moment, thus you need to be treated with a different response than that given to someone neurotypical.
I don't know if the US has these cards, but one thing you may want to look into is asking your doctor if he or she could compose a brief letter stating much the same thing as the cards state. You could carry that with you for situations like this, and it would carry more authority than if you printed out something yourself or made a homemade card.
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