I think i like a person of the same sex

Ok... where to begin? First of all, I'm going to keep my gender a secret for mostly personal reasons. Also not going to use real names, but that's probably self explanatory. So, let's say there's this person I met online. We've never really talked outside of chat rooms and that kind of stuff, so I know next to nothing about them. And yet every time I think about them I get a kind of flutter in my heart. Sometimes we joke around about relationships but I think I'm actually developing feelings for them! Now this wouldn't be so bad, if it weren't for the fact that we're the same sex!! Now I know for a fact that I like the opposite sex, and I've never EVER had these same feelings for another person of the same gender before, so you can see why I'm a little confused. I kind of, sort of, want to be with them, but I also am deathly worried about... well everything. So what do you guys think, is it normal?