t sleep or the weather is bad, or you had caffine and many others etc...
exercise may not be good at the moment. 2 min. on the
bike (slow speed), walk down a few stairs, fold some towels and your done for the day. You need to listen to your body very carefully and don't overdue or underdue anything. I'm still angry with my body because it doesn't act like it used to-and if I don't get over that, I'll be stuck in bad place.