A Were Wolf Story

I need a fifty page young adult fiction story where a young female named Amanda is bitten by a one of her female friends name Tristy at the high school. The young girl is part of a crew of chicks who are really were wolfs but she had no idea until one day she got noisy and followed them out to the woods on a full moon. She tried to hide but was spotted once they chased her down and found out who it was they made her an choose either become one of us or die .