Thinking about something you did and in "retrospect" regretting it.
By the way thought of this after seeing the "expression" (not even a word) fucking retrospect. Seems kinda crude. Challenge folks to be me more creative!
Two guys talking several weeks after a wild night out in Vegas.
The mixture of feelings of bitterness, sadness and regret when you realize a song lyric, scene from a movie, or some other kitschy moment is indeliably etched into your memory, wasting those brain cells for more deserving works.
I just heard Elton John's "Ticking" for the first time in probably twenty-five years and I recited every lyric, what a terrible regretiniscence.