Some Call It Old Age

Sometimes, it's just this....I'm dumb, or forgetful...or just one of those days that I can't remember my first name.
Today was one of those days... feel like I'm getting nowhere fast and stuck in one place that no longer seems familiar to me.
Then there are these days...when I am playing the piano and can't remember where to put my fingers...the keys no longer look right.
Or, I'm singing a song I have song hundreds of times...and I can't remember the words.
Or, the roommate I had in college reminds me of something that happened 30 years ago and I can't remember what she's talking about.
Old age???
Brain fart??
Both??