I just take a step back from whatever is bothering me, I breathe in and out a few times and just let the emotions and anxiety wash away. Then, after a few moments, I just start thinking logically on how to deal with the source of my stress, and I get down to work on it. Only if I had the energy.

Or, I tend to go for comfort, so I seek comfort in things such as games or head out to bed. Sleeping can always calm my nerves down. Listening to some music also helps, as it eases my mind.