Sometimes you just need to stop for a moment and realize that there's NOTHING that really matters. If your problems have a solution, then you'll eventually find it. If they don't, why worry about them? Plus, keeping a calm mindset always helps coming up with better ideas. So I would suggest simple things as having a nice tea, going for a walk or taking a nap. I am not the kind of person that's good with mindfulness, but it helps for maaaaany people. Last advice: don't spend to much time in front of a screen, it adds up to your stress levels.