DAE dream as a different gender?

In a lot of my dreams (that I remember) my gender is irrelevant to the crazy storylines unfolding around me. However, last night's slumber was an epic saga of anxiety after accidentally impregnating a woman.

I am female.

Considering this absurdity upon waking up, I then realized that in most of my dreams where my gender IS specified...I am a male character. In real life I am 99% heterosexual and have never had any masculine or androgynous inclinations. I have always felt like a woman inside and out. (Hell, I'm wearing a dress at the moment.) Soooo...WTF BRAIN?