Disclaimer: I'm not actually a ballerina.
I just play one in my fantasies.
Is it possible to be a male, and want to be a ballerina, but not to be a male ballerina? (Ballerino?). I mean, there are ballet parts for men and for women, but they're typically very different. The moves are different (and this is where the physical differences between men and women probably come into play), and the costumes are different. There is a place for men in ballet, but it's not the same place that women have in ballet. So what if you are a man, but you want to be in the women's place? I'm more feminine than most men, but I think I would look a whole lot more ridiculous in a male ballet costume than in this pink tutu, which I think looks pretty good on me. (Or is that because I feel fantastic wearing it?).
This reminds me of Revolutionary Girl Utena's desire not to be rescued by a prince, but to be the prince (and not a princess). But, obviously, in the other direction. It's still more acceptable for women to want to be like men than it is for men to want to be like women. Because wanting to be rescued is considered a weakness. Not that this is an illogical view, but we can't all be the rescuer, or there'd be no one to rescue! There can't be any value in rescuing unless there is some value in needing to be rescued. Feminism: "girls can be just like guys", instead of "girls are okay, too". You know, just the way they are. Pretty princesses and everything.
Aside: As I feared (although this might not be a bad thing), with my new iPhone, the line between my selfie photography and my "real" photography is already beginning to blur.