Even bad lessons are good….and help you get better. I found this to be true. When I have a bad lesson, I analyze it and sometimes it just means I need to take a break for a couple of days from working so hard….give my mind (mostly) a break. It usually works for me. Instead of digging into my literature and etudes I just play for enjoyment for a day or two. It does wonders.
Also, for me, my lessons are always much better if I am not doing 10 gazillion things that day beforehand. Normally, I get up at 5:00 am, teach elementary and middle school music all day (that alone is enough to blow your brain to the moon and back), zoom home, take the dog out, feed him, take him out again and play with him, play through a piece or two, zoom off and drive 40 minutes through rush hour traffic