Blah has Turned into Emotional Wreck

Ok - so I thought I was just feeling blah, but maybe I'm way more emotional right now than I've even admitting to myself. Case in point, I just had a "disagreement" with my graphic designer here at work. By the time I got off the phone with her after an increasingly frustrating conversation, I was in tears and had to close my office door so no one would see me crying. I composed myself and then went down to discuss the situation with my boss and to offer up a solution to help the work process run smoother in the future. However, as I was trying to explain the situation to him, I completely broke down in tears and starting crying in his office! I have never done that and I'm quite embarrassed. So, now he's thinking this issue with the graphic designer is much bigger and upsetting than it is. In fact, it's just a minor issue that can be easily fixed. Nothing worth crying over. Thankfully, I eventually regained my composure and explained that I wasn't crying over that, but for some reason I was just emotional today and then we went on to have a calm, productive conversation. Ugghhh...I feel like such an idiot and I feel like I've completely lost control of my emotions right now - I'm starting to cry again and I don't know why!