So I want to get my fallopian tubes removed?

I don't mean cut i mean completely remove. Because i read you have a chance of getting pregnant even after it's cut because it seals back up. Anyway I have decided i never want kids and you will say but maybe later on in life no i have Always hated kids i have loved animals more then people. Kids are too much and so will i have to wait till I'm 18? I'm 17 almost 18 or what? I am terrified of getting pregnant.