I can identify with you, SilkySifaka, and Atomsk. I don't like mirrors, and I don't like my own reflection, never did. I also get a 'shock' when I happen upon my own reflection somewhere, just like Sifaka.
As a cleaner, I sometimes have to clean mirrors in bathrooms, and I always position myself so that I don't have to directly see myself; I always avoid looking directly at my own reflection.
I'm reminded of an autistic young man who was on a TV show some 15 years ago, and who disliked seeing himself on a video recording.
EDIT: I should say I don't find myself particularly unattractive or anything like that, so for me it's not tied to that.
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