Good days and Bad days

Some days are just good. I don't know why. I have no idea what happens in the world to make it a good day. I am not saying these days don't have any bad in them, but somedays are just infinately easier to deal with what the world throws at you.
Today was a long day at work, problems arose, and I didn't get enough lunch (this last one is usually the case). But I felt like smiling the whole day. And some days, even if everything goes smoothly, I can be the biggest grumpasaurus ever. I don't know why. I just don't. Today I decided to stop trying to figure it out and just enjoy.....