The Ghost in The School Bathroom (Story Time)

I remember being in second/third grade in this new school. The bathroom had a wall of stalls and two mirrors facing each other across the room. I would go to the washroom and wash my hand at the far wall away from the door. Walking back id see a flash of something going through the stalls. I turned my head and saw myself but I was wearing different clothes and hair. It was really off but whenever I went to the washroom she was always there. I thought I was going crazy. I never told anyone until a friend of mine came to me freaking out saying she saw herself in the washroom. I couldn't believe it, we tried to see it together but she would never show unless we were alone. Eventually I switched schools and never saw it again.