I can exhale through my mouth, or my nose, or both at the same time. I don't choose it consciously, but I can if I want to. I did the same with cigarettes and my kids always made fun of me looking like a dragon. I find that I exhale more vapor through my nose, the same with cigarettes. It's just automatic but it does help with flavor.
P.S. I'm a girl, too.
P.S. I'm a girl, too.