Maybe it's a tic?
Tics don't have to be forever, they can come and go in times of stress. A temporary tic was one of the only things my granddaughter exhibited when she was so depressed. Once the anti-depressant started to work, it went away.
I get facial twitches when I'm stressed. They resolve on their own as the stressors pass, but are very irritating when they are happening. They have lasted up to two weeks, in the past.
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Disagreeing with you doesn't mean I hate you, it just means we disagree.
Neurocognitive exam in May 2019, diagnosed with ASD, Asperger's type in June 2019.