Ugh.... please help me out here??

Ok, I'm in 8th grade, and at the end of the year our school is taking a 3 day trip to the state capitol. We're only allowed to have 4 people stay in a room. Well I sit at the lunch table with 4 other girls. Karleigh is being really mean to Annie ( both of these girls sit at the table ) So, Annie, Laura, and Hailey asked if I would room with them instead of Karleigh and I said sure. Now Karleigh is being really mean to me about it and its not even my fault. What should I do?