Please help me.?

Hello. I'm a 16 year old boy. Ever since the age of 13 i watched and masturbated. Ever since i was 8, girls were the only thing that I could think about. But, I'm starting to notice that I'm not as attracted to girls as I was. Is this something that could change in me? Or is this just probably a phase that i could overcome by trying to stop watching ography? I am still attracted to girls, but not nearly as much as i used to be. I'm really startin to worry about this. Any answers would be greatly appreciated. Thanks