Go treat yourself to something small, even of its just a walk to the corner store for a chocolate bar. The natural endorphins you'll get from the walk will help elevate your mood, and then the treat will help too. You deserve it!
Sorry to hear you are having a bad day. I know what you mean about the weather. I made myself a root beer float for dessert and put on a funny movie to 'lift' my mood. Hope tomorrow is better...