Shapeshifter

After being laughed at by two girls she looks up to, Zuri runs to hide and stumbles upon a mysterious red tent full of caricature drawings. Next to a mirror she sees a drawing that looks oddly like her-- but at her worse.
Driven by shame at how ugly she feels, she begins pulling at her face, becoming more and more erratic. Suddenly, at the peak, she changes. The girl in the mirror is someone else.
How has she shifted, and what does the tent, and the artist who runs it, have to do with this change?