Did something bad to a x friend HELP PLEEAEE!!!!?

ok so i had a friend and she always thought she was more popular than me and so when i became popular she was doing all this mean stuff. she made screen names and aimed me and my friends pretending to be other people and saying stuff like i hate you blah blah blah then she wrote me a note saying i cant wait till you move and good job taking all my friends, good luck at getting to my new friends they don't like you BLBLAHHH BLAHH. i just really wanted to get back at her so today i made a sn that was football and stuff and then at the end she was like i know who this is. don'ttt know if she really knows or not. but now i feel bad and im scared. what should i do??haven'ttt talked to her in a year!!