Usually, you feel sad when you get into a fight with a friend, nervous before a big test or interview, and happy when you win at a contest or see a long-lost friend. In your mind, you might think you are in control of what you feel because you understand the causes of those feelings. But a lot more goes on inside your brain! As time passes, our brain gathers more information about who we are. The irony is, we often change as well, so the information about you changes too. You be sure though, that your subconscious brain keeps everything!