Hi Eddie,
I think everyone here can empathise with your pain and that overwhelming (and yes torturous!) feeling of panic and anger which can wash over us during triggers.
However, as you say, it’s never acceptable to hit anyone. I agree with Mystic Fupa too here. It might be worth gauging who you tell about your misophonia. I actually never told anyone at my school because I knew kids wouldn’t get and that worse, they might use it against me and it could have the potential to create the kind of conflict you talk about.
If you have the faintest inclining that you’re leaning towards violence in the future, the easiest, fastest and safest thing to do is just remove yourself from the situation.
As others have said, leave the room, walk away… make an excuse and go to the bathroom.
When you’re alone again, splash your face with cold water, take a deep breath and reset yourself. As you get older you’ll find that you can slot into coping mechanisms like these easier.
You can absolutely do this.