Yup, we've all had a few of those... Sometimes it can be fixed, sometimes not. The trick is to look at it objectively and decide if there is anything you can do to improve the situation despite the cause.
Sometimes you need to put on those lounge pants and go grab a big tub of icecream, scoop a big chunk out, cut up some bananas, bring out the sprinkles, set it on your side table.. put on some good music, blast it, go sit down, grab that bowl, and dig in!
My bad day was Friday. Nothing that happened could turn my mood around. Today I feel much better, thankfully.