It's true, I've been told that I'm not a femme by someone (happened to be FtM) from the match site. I think the reason was that I expressed to him that I appreciate all women, not just butch women. Even though butch women are my preference for romantic or sexual partners.
But, whatever. It bugged me because I thought he was a jerk to offer his opinion. I was amazed (naively) that someone who had defied stereotypes, as he had, would be so quick to label and judge me. It didn't affect how I felt about myself, though. I can have low self-esteem without any help from anyone!