

Joking aside, this advice comes from epictetus Manual (also known as ‘enichridon’ or ‘handbook’). It’s very short, effective and (contrary to a lot of latter philosophers) very easy to read and understand. It helped me a lot fight my anxiety, you should be able to find it for free on the internets. Worth reading, in my opinion.
https://classics.mit.edu/Epictetus/epicench.html
There, there. Everything is going to be the same but you’ll feel a bit less anxious about it. It will help you focus and chose to act where you actually can make a difference.