Is it normal to love someone of the same genders..??

Me and this girl have been best friends for only 3 years. No exaggeration, she's absolutely gorgeous...she's an athlete, has an amazing voice and she's always so funny and really genuinely nice. She would always help me with my work and we'd usually sit really close, like knees and shoulders touching which I always felt strangely comforting, and we used to be together constantly. I failed my exams last year and had to retain, hence we were split but we were still close. The thought of not being in the same class's with her made me really really upset. A lot more upset than when i broke up with a boy...It freaked me out a little. After that, I started questioning my feelings for her. I have only ever been with boys, and haven't really found other girls attractive. But I'm not going to lie. I find her immensely attractive and almost even kissed her once...