The Necromancer's Prison by Alec Whitesell and Craig Bonacorsi

She wanted to find her place in the universe. She never imagined it might not be on Earth. When Emily Murphy over slept the morning of her college entrance exam, she thought missing her test was the worst thing that could happen. She never expected she would wind up lost halfway across the galaxy, battling aliens with laser guns and mages hurling lightning. Like most seventeen year olds, Emily’s main concern had been navigating the perils of high school, not surviving shootouts and sorcery. That changed when her school was attacked and a student was kidnapped. While everyone else smartly fled from danger, she recklessly ran toward it mounting an impossible rescue that would lead her on a journey unlike anything she could have imagined. Dropped into a strange world teeming with merciless criminals and ruthless aristocrats, surrounded by violence and betrayal, Emily must untangle a web of intrigue and deceit to solve the mystery behind the abduction, save her classmate, and discover the destiny which awaits her. It is either that, or die trying…