I have found noticeable differences in how I wake up. Sometimes terrified, sometimes despondent, sometimes energetic, sometimes lethargic, sometimes ready to give up, sometimes as if iron chains of worries and fears are not letting me get up. This may also change in the course of the day for better, for worse.
It must be the complex brain, psyche, chemistry, etc. Who knows? As long as I get some good days, good periods, I go with the flow. Accept what is and keep on working with my methods of doing the best I can for the brain, that mind-body connection. Just my experience.