As MollyTroubletail correctly points out, an attraction to a single individual tells you little. When it is someone close to you (such as a sibling's friend) then that is even more the case. The attraction can be rooted in so many other aspects of the person's personality, and their physical sex may be quite a secondary thing.
As for sex seeming weird, just remember Alan Rickman in Dogma:
The Metatron wrote:
There's nothing funnier than the faces you humans make mid-coitus.
Sex is a behaviour that you may (or may not) grow into. There will be people and activities that appeal to you, and there will be others that don't. But the important thing is that
you will develop
your own sexuality, and
you will come to understand it.
_________________
--James