Am i turning bi or worrying to much?

Hi can someone help me out pls. I am 15 this year and jus 2 days ago i found out that some of my girl friends turn out to be bi and now im afraid i would be one too, i mean ido not get by guys and do not get horny overy them but im just worried as thoughts just keep popping in my head and im disgusted by it, i watch and like girls, get horny over them and i have a girl which i liked or loved since last year, am i worrying too much or am i turning bi? i do not have any dirty thoughts about guys but i do about girls, everytime i see a hot chick wearing mini skirt or low cut, i would walk closer to see her bra or try to , though never successful, i dun feel anything towards guys but jus thoughts keep popping in my head..help pls, I AM 15 THIS YEAR...thank you