By nature of me being ADHD, a lot of my ocs end up with it or mimicking it, but two who are actually on my toyhouse right now are Luda and Pan!
Luda has PTSD, partially from her childhood and from being enlisted in a war, mostly manifesting in nightmares and also how she carries herself. She's pretty much always in a state of being tense unconsciously, even when she's joking around/in a good mood. One of her triggers is people moving fast behind her, and she does very badly in crowds, especially since she's much shorter than the average human and can't see what's going on around her.
Pan meanwhile, has a lot of anxiety, most of which they've internalized and repressed, mostly manifesting in them trying to relieve it through physical means (religiously sparring and practicing). They're also very bad with touch except for dragons they know well or are related to, and almost never initiate physical contact.