How to remain calm 4 years in

I’m in my 4th year teaching high school history. I am teaching an upperclassmen US history. It’s the en of the day and for the most part I like the class but today they set me off. Notably two of my upperclassmen boys were just completely obnoxious. They do not care the one has shown up once a week for three weeks and today tried to flirt with 9th grade girls (shooting that down) the other comes in and does not care. So they both came I. Today. Here is hoping none of them show up at all the rest of the week but I gotta feeling they will be an inconvenience all year. Advice on how to keep my calm when exhausted and dealing with those kids who will fail and only show up to cause chaos