Why do i have hooves?

For a year I had been staying with two strict foster parents who I didn't really like. One of them was named Aurora and the stallion was named Ice Pop. I couldn't talk back, and every time I said something about being a human I got grounded. That's why I am currently sitting on my bed in my new room with my hoofs crossed. I looked around observing the colors and things inside when  Aurora came in.

"You're going to start grade one tomorrow" She said.

"I've already been to grade one. In fact, I already finished primary school!" I replied slightly irritated but getting used to being treated like a little kid. She replied saying I haven't and that it's bedtime. I didn't want to get punished in this boring room again so I went to bed.

      The next day Aurora shook me awake and put a frilly pink bow on my head. I was about to take it off when she stopped me asking me to do this for her. I replied with an eye roll and kept it on, and she walked me to school. When I got there i sat down at a desk and ignored the teacher. Then I got called on.

"Violet what are we talking about?"

"Uhh.. Colors?" I replied surprised, and everyone started laughing at me so I stuck my tongue out which got me a visit to the principals office.