Feelings for a friend..thats a girl?

okay well im 14 and mai BEST friend since preschool told me bout a year ago that she liked girls and guys.i thought i was strait. but.i have feelings for her that id have if i liked a guy.nd i love her.nd yu cant say **** bout me not loving someone too soon ive known her for more than 13 years!! LOL but i told her how i felt nd she said she liked me too but..ther is this other girl..that she likes too.nd i cant stand it when she speaks of her :( like may friend was fine with it she even said we could date on and off and we could try some stuff.but.i dont want it to be just little flings! ive never felt this way about a girl..im so confused...HELP!! :'( WAHH DOH I DOO!?