How can i get revenge on my ex boyfriend?

okay so my ex broke up with me about a month ago and we have been good friends ever since. we would joke around with each other and everything and then he stopped talking to me so i finally texted him asking if he was mad at me and he said that it was akward texting me when he had a girlfriend and then he told me he was dating a high schooler, but i don't believe him because we are both only 13. he said he didn't want to be my friend anymore and i want to get revenge. any advice?