Rant/Vent- If something is bothering you or crossing your mind again and again, write it on a paper or tell it to someone else. They will either just listen to you, it soothe your pain. Also, they might say something consoling or encouraging.
You’ll realize that the problem wasn’t really that big or even if it was then too its okay. Rather than overthinking, get it out and calm down.
[I usually (always) prefer paper over people]
Though the problem with paper is that it listens to you with all its heart, but it doesn’t care encouragement part. But then you need to do some things by yourself.