As far as a I understand it (and you probably already know this, but allow me to tread known waters for a moment), Brony is an amalgamation of Bro + Pony, initially used on 4Chan ironically, but has since been adopted by the fanbase. As I stated above, there is no rule to state that a woman/girl cannot be a Bro; thus, calling yourself a Bro or Brony would be perfectly acceptable. I believe the aforementioned term "Bro" is used to describe someone in with the crowd and always has his/her friends backs.Playful Pony said:Hm. I just assumed that bro was short for brother Oo. And that I would be a sis? A... Sissy? No wait, that's something completely unrelated... I guess that does answer my question, thanks! =3 I'm still not a Brony as such... Is there no fancy title for people that just like plain old regular ponies?
However, we (that is, the Brony crowd), take a slightly different view on this, ala you can call yourself whatever you want. Brony is used to describe a fan, the fanbase, or a male fan specifically. Some female fans prefer to be called "Pegasisters", while there are still others both in and outside the fandom (like you), who just call themselves fans.
The point of this long winded reply being: You can probably just get away with calling yourself a pony fan.