I have genuine feelings for my best friend of the same gender. (girl) HELP!?

(PLEASE READ THE ENTIRE STORY BEFORE YOU JUDGE). alright, let me start off by saying i am 14 and my best friend is 15. we got really close last summer and have stayed close ever since. we spent at LEAST 5 days of the week together. and still do. i told her about a previous "thing" i had for another girl, but also told her i was no longer interested in girls. truth is, over time i started falling in love with her. now it's gotten to the point where no matter what i do i'm thinking about her. (SHE'S STRAIGHT). i know i am "too young" for love, ok? i know this. but it's real. every chance i get, i stare at her beautiful face. her personality, her beauty, her sense of humor and her smile. i love absolutely without a doubt love everything about her. her imperfections even make her perfect to me. i try very very hard to hide anything that could give her the idea i love her. because i am so scared that she will not want to be my friend anymore let alone my girlfriend because of the awkwardness that will follow. you know? and i could understand why she would feel that way. because i always look at her in admiration (when she isn't paying attention). but it's getting so hard! now i can't hardly control my eyes when she undresses in front of me, for whatever reason, i'm extremely attracted to her sexually as well. i mean we play fight a lot and often times she'll sit on top of me to pin me down, is it bad that i get soo "excited" when she does that? or even sleeping in the same bed with her i just lay there and wish something would happen. we played truth or dare once. truth is, i only wanted to play it hoping someone would dare us to kiss. just being honest guys. i feel so guilty. am i wrong for feeling this way for her? she's seriously the best thing that's ever happened to me. i have been in foster care most of my life, and never had the chance to make permanent friend. there isn't anything i would change about her, she's perfection. and there surely isn't ANYTHING in this world that i wouldn't do for her. she has no idea how she makes me feel just by touching me. she even sometimes makes me feel insecure (unintentionally). being that she's completely flawless in my eyes.....it makes me feel like i'm not good enough for her. maybe even ugly. i love being around her, but when i am i hide the feelings. don't get me wrong, i am truly her friend, and will always be there for her even if she rejects me in the future. but it would make me the luckiest person in the world if we became more. how do i tell her? or should i? it's gotten to the point that i'm asking people that don't even know me for advise...so please please help me? please.