Is this the real thing or is it just a phase?

well a while ago me and my best friend ( were both girls) kayleigh kissed when i slept over at her house and we never talked about it for about a year then she suddenly kissed me again and told me she fancied me and i was happy cos i fancied her too so she asked me out so we went out but then the next day i told her that i wasnt sure and i needed to think about it cos i was still coming to terms with the whole thing, so then we left it for a while and then she asked me again and this time i said yes and then again the next day i told her that i wasnt sure but she told me to go with the feeling and block the nerves and doubts out so i tried and it worked so now we go out with eachother and weve kissed a few times and had heart to hearts but whenever we see a fit guy were like ooo hes yummy :p but if were both going out is that acceptable to think a guy is fit? oh and the whole me a kayleigh is a secret because were not ready to tell people yet so everyone thinks were straight but its making things a little difficult cos when where together at her house or vice versa we have to be careful about what we do or say.so that night when we had a good talk before we got together i asked her if she was deadly serious about it and she said she really was serious so i said i was too and i am but im wondering is this the real thing or is it just a phase we will grow out of oh and if it helps kayleigh is just 16 and im 16 turning 17 next april, so what does it sound like to you is it real or is it a phase? cos she says she loves me a lot and i sayy it too but its more like 'luv ya' more then 'i love you' but maybe thats cos its a secret? please help and no silly answers please! thanks love you all :)