I've had that happen, too. Sometimes when I've cut off my beard or goatee -- weird. Once I cut off my mustache that I've had since I was 18 "Who is this child in the mirror?"
I had it happen most often when I was leaving the Truth ™ & going thru a horrendous divorce, it did seem I "didn't recognize myself". I suppose I was really morphing into another man, my values were changing so much.
And I have epilepsy, so it also feels surreal at times after seizures...looking in mirrors. Other people here with epilepsy will understand that.
And besides that, I am certifiably crazy. And so are you Dave.
So there !
Rabbit