How to Get Over Fear of Parkour?

I really love parkour and want to take classes but there are absolutely NO schools near where I live except for Toronto but it's an hour away from where I live. All I really want to know if how to do a flagpole, a kip up and my favorite one: a wallflip (Backflip off a wall). I can do monkey vaults pretty well but I just really want to learn wallflips. I've wanted to do wallflips ever since I saw it on Youtube. The thing is though, I've never taken gymnastics and every time I try to flip backwards on my wall, my fear just gets to me. One single time I've been able to almost flip but I fell on my back. I don't have any fear of heights I'm just afraid that if I flip I'll break my neck. I just want to do it so maybe I can perform it for a talent show and my school this year. Any advice on what I should be doing aqnd what I should practice on? Also, I don't have a trampoline or anything like that. I saw these videos on Youtube but only one of them was a little helpful, but even that one was confusing. Here is the link: a href="http://www.youtube.com/watch?v=8dGZos-8fD0." rel="nofollow"http://www.youtube.com/watch?v=8dGZos-8f…/a Also, my backyard is on a hill but I can do it inside or outside somewhere. Longest answer and most specific/non confusing answer will get best answer. BTW, I'm 13.