I would really like to repress this memory...?

I had with this person, and I really wish I didn't, I don't really want to talk about it with anyone because nobody besides me knows them, they don't even know I do and it would just be horrible, worse then it is already. In all honesty, it was one of the stupidest decisions I ever made, and I don't want to remember it. I want to know how to repress this, I don't care if it surfaces later, by then I'll have left this place and never have to see them again. I am 14 is it still possible to repress it? Please give me a technique to, and not trying to deter me from my goal.