You don't have to label yourself. Just be who you are, and love whom you love. Love is always good, even if it's different, even if it conflicts with how you're used to thinking about yourself - love is the greatest gift anyone could ever give or receive.
Some day, you might want to describe your sexuality to someone else, and you'll have to find the label that best fits you. Maybe it's bi, maybe it's straight, maybe it's lesbian. It doesn't matter. It's just a label, a shorthand to help other people think about who you might be attracted to. It doesn't define you, it only describes you.