Psyching yourself out of throwing tricks

Hello, everyone, I was wondering if you people have advice for me. I am trying to land a double backflip off the kicker but my mind in stopping from even attempting the trick. I know I can do it, my mind just won't let me. I am hitting a mental barrier. If you have any advice on how to just throw it and not be scared that would be great. My name is Ricky and I am 17.