I would continue to self-soothe as well as I could, remind myself that "this too shall pass" and try to concentrate on going out with friends later or whatever it was I wanted to think about instead of how miserable I felt. If you were feeling bad yesterday, it could be related to something yesterday or that happened earlier or something happening later in your life or could be dietary, I would play detective (to forget how I actually felt) or just endure it until something else could take its place.