I don't know what started it this time. I have been getting back to my regular exercise routine and this has felt good. I reminded myself that the change to my mental state was the best reason to exercise and I just talked myself into it one day at a time. I know this works.
I think, though, that when there is an up there is a down. It's a way of slowing the progress, making it more real. Whatever the reason, I am not feeling all that bad.