My advice is to stop stressing about it. Chances are, you will stutter but why spend days and days stressing about a situation that will last 10 seconds? Try to forget about it and stress about it when it comes to it. I’m 22M and have worried all my life. A couple years ago, I clocked onto it and decided to change. I stopped caring simply by choosing not to think about it. My stutter is still exactly the same but mentally, I’m in a way better place. Try to just chill a bit. Stressing gets you nowhere and it will only make you dread tomorrow more and more. My stutter got a lot worse the day I turned 21. I think I was juggling too much at once - job and college. It’s never gotten better but to be fair, I still am constantly burning myself out with the same reasons. Breathe a little (metaphorically and physically) and you’re stutter will die down again. Good luck for tomorrow. Have a chill night and keep your mind busy with something else!