A big problem for a straight person?

hi im a college student and am as straight as anyone. i love women and used to have a big reputation as a bit of a player.yet i changed that recently as that tag was annoying me so i just became me without all the dlirting and stuff. theres a girl whos been at the college about 3 months and we kind of talked at first and recently we were put on a project together. thankfully she got to see the real me and she is hot but then she comes out with today '' so erm, are you gay''. so heres me hoping to pull her maybe and she thinks im gay. so i told her no and why she thought that and she said that she just has one of them feelings, and so does her best mate. i never speak to her best mate and i asked why she thought i was and apparently my eyes glint when i talk to boys. then i ask everyone, all my friends and people i know and there like your the most un gay person i know but there saying that because they know my past with girls. so are there any characteristics that i could have which could show im gay, and how can i convince her im not because even if i get a girlfriend she said she thinks ill be covering up the fact im either biual or gay. thanks for all your help.