A childhood belief about ghosts

I've heard a lot of differant stories about "Bloody Mary". My best friends and I have tried the ritual before. We all crammed into a the bathroom, with the door shut and the lights off and we said, "Bloody Mary, I killed your baby!" Five times. After the fifth time...nothing happened...I think...We all ran out fo the room screaming before we could even wait a couple seconds after saying it the fifth time, But I heard a story once...about a girl Who tried it. They say that she went into her Bathroom, closed the windows, and shut off all the lights, and closed the doors. After saying the words five times....In the mirror there was a face of an 18th or 19th Century woman in the mirror. The girl got scared and turned away from the mirror. She looked back and Bloody Mary's bloody nails were reaching out from the mirror. The nails were EXTREMLY LONG! Bloody Mary scratched the girls spine and ripped off the skin on her back. She died intsantly. I'm not sure if it's true...but I used to believe it....