It can definitely be tricky to infuse style and personality into a small room, especially when there are limitations in place of how you can decorate! If you’re not sure what color you want to paint your walls yet (and this is a decision you should take your time with!), bring some flair and edge into the space with some rad wall art instead. You could DIY some (I have tutorials here: http://mrkate.com/2016/02/23/diy-finger-painting-wall-art/ and here: http://mrkate.com/2016/01/14/large-scale-wall-art-peyton-list/!) or go to a site like Society6 and have fun picking the pieces that represent you best.
If you want an edgier aesthetic in your room, keep your eye out for some cool metallic pieces. Gunmetals, golds, and platinums are all edgy, and when paired with patterns in deep colors like burgundies and blues (maybe even a 90s-inspired plaid) really bring in that grungy glamour feel, too.
I hope this helped! Let me know if you have any more questions and how everything turns out!