Teenage Girl Bedroom...?

Hey im 14 and i am getting my bedroom repainted for my birthday. I am also going to get more new furniture and decorations. At the moment it is lilac and cream, with some youngish furniture but Im getting onto 15 so I want it to be mature. Im not a girly girl, but im not a tomboy either. Please can you help me think of some themes, colours or ideas for my new room. Any pictures or links would be great! Thankyou x