If she was going to punch you in the face, you have a right to black yourself! Lol! But really, everyone know the saying "Sticks and stones may hurt your bones but words can never hurt you," and sometimes its not true. But in this case, it is. Just one swear and she tries to punch you. But on the other hand, you shouldn't have sweared at all at her, and now shes mad. If you liked her, why did you swear at her? You should say sorry and write a sorry note, too. Thanks, Monchi
P.S. If you apologize, it may take a while for her to feel happy with you again. Give her time, and eventually SHE may say sorry, too. (because she should)
But punching and swearing are wrong so don't do it.