Oh yes, I've done that a few times, but I started doing it way before I got "old". Should I be worried?
I like to think of it as a practical joke I'm subconsciously playing on myself; that moment when I open the cupboard, see the milk and think "hah, at least I know where the tea bags are".
That's usually the time when I decide to remove the old goat's silvery beard using my rechargeable shaver/trimmer, which then usually runs out of charge before I've finished the job, leaving me with this rather er 'natty' asymmetrical look...