Write your plan on a notepad or excel sheet. That way, all that's on your mind can be visualized for easy thinking and you won't have to spend too much time thinking over and over again.
Do something or activity that pleases you
You need to rest your mind from something that takes your energy and your time. You may need to do your hobby that pleases you. This can help in diverting your mind for a moment to something that can refresh your brain.
Maybe you can do sports. Yes, exercise can help free your mind from negative thoughts. By exercising, you not only refresh your body, but also your brain. No need to do in natural time, 10-30 minutes may be enough.