Hmmm hard to say really. You have to reflect on the events that occur between your initial mood and your later mood. With me it can be anything really. Sometimes I get suicidal and then I have lunch and am just fine. Other times, I watch a comedy or play a video game. It kind of depends on what you do and what emotions they are tied too.
For example at work, if I am having a bad day, I feel more suicidal. This is because I am depressed about the state of my current job. However, when I am at home and I am playing a video game, and am angry at it. I am angry because the game is difficult not at the game itself. When I am done playing. I may be upset, but I am not depressed. Because I know I am really good at video games.
The human mind is weird.