Not everything in life is rosy. We all have our good days and bad days - there's no need to make a big deal out of a bad day.
Everyone has their ups and downs. You need to accept them. And if you start out in a good mood things are far more likely to go your way!
Mood swings are a totally natural phenomenon we should just accept. As long as you don't play the victim, they always go away after a couple of hours or a couple of days....