I always thought I was a girl?

So, I was watching A Christmas Carol with my sisters and dad today, and then this conversation came up:

Dad: Let me see your hand.
Me: *takes out hand*
Dad: See, you can tell a man from a woman if you look at the length of their index finger and ring finger. A woman's index finger is longer than their ring finger, and a man's ring finger is longer than their index finger.
Me: But dad, my left index finger is shorter than my ring finger.
Nat: Dad, it's just genetics! Here, this is how you tell a man from a woman. Charlene, stand up.
Me: *stands up*
Nat: Look at the bottom of your foot.
Me: *looks at foot*
Nat: No, you did it the wrong way! That's how a guy looks at their foot!
Me: Dad, I think I'm a man.
Dad: *to Nat and Maine* I don't know what happened to Charlene.