Many of us think that emotions come from our psychology, very often though, they can also come from our physiology . That is to say that our emotions are dictated by the things that are going on in our bodies.
If you are in a bad mood then it could be because you are low on blood sugar, our bodies use high blood sugar as a signal to create "feel good" hormones, when he drops we produce cortisone, which makes us anxious and angry. Your might be tired too, or perhaps your emotions could be getting in the way? Either way, you need to consider the role of your physiology, as well as the role of your mind.
Control Your Thoughts.
That said, controlling your thoughts is also important. Techniques used in CBT( cognitive behavioural therapy) teach us to challenge negative thoughts and to even test our unhelpful believes. This means first identifying the things we think and the things that are causing our bad state of mind and then asking whether those thoughts are true or useful.
They are countless good reason to meditate, one of the most important is that meditation can improve your emotional control, your focus and your discipline. This is literally a process that involves focusing your mind and avoiding distracting thoughts. And if you can do that, then you can avoid distracting emotions as well. In the short term, about of meditation is a great way to calm your racing mind. In the long term, it is a powerful tool for enhancing your emotional stability.
Oscar Wilde said:
"I don't want to be at the mercy of my emotions. I want to use them, to enjoy them, and to dominate them."