Do I really seem that gay?

It is very bothersome because I'll be around alot of attractive girls and none of them at all ever see me in a ual way or anything like that. It's not because I'm ugly or anything I've asked around and alot of girls say that I'm very cute but i can NEVER get a girl to like me and have had several (atleast 11) ask me straight up if I am gay. I'll be honest I am rather metroual and have been told I have very nice posture, I never slouch, etc... but never anything to gay. I don't speak like I'm gay or dress like it. I'm not against gay people but it is annoying to be confused as one when I am in fact not... please give me a little advice on what to do or how to convince a girl that I'm not gay and possibly get a girlfriend, I have had a couple girlfriends before all this started and I really don't know why it started in the first place... also I'm 15 and a sophmore in highschool and for the most part it started my freshman year if that helps