How am I in the wrong?

Can someone for the love of God PLEASE explain to me why I could get in trouble for screaming the F word at a customer AFTER she literally put her hands on me?

I got in an altercation with a customer on my lunch break and when I tried to walk away from the situation, she grabbed my shoulder to stop me from walking away and I screamed, “DON’T FUCKING TOUCH ME. DO NOT FUCKING TOUCH ME.” And walked away.

Why is it that all my work cares about is that I said the F word? Someone put their hands on me. I was just reacting.