How can I change up my style?

I'm in middle school, but I'm sick of wearing a graphic tee and jeans everyday. I have a few different outfits, but only 5, and i can't wear them that often because I Don't like to repeat things often. Any stores or online places that i can change up my style? I don't want to spend a boatload of money either. And I really like the Selena Gomez/Demi Lovato/ Boho Chic looks..Please help!