Spehss, are you past me that time-traveled forward?
Regardless, I'm going to give you the verbal kick-in-the-ass that past me should have gotten.
1. Stop projecting forward into horrible "what-if" scenarios. You aren't Muad'dib, you don't see the future. You can, however, trap yourself in potential futures and use it to rationalize not doing anything because you're scared. Some people spend their whole lives doing that.
2. Be confident. Be honest. You're bound to run into her again in the near-future, ask her if she wants to grab some lunch/dinner and then just talk to her. Ask her about herself, where she's from, etc. Let the conversation open up naturally.
3. After doing this a couple of times, ask her out to see a movie. Or maybe to go look at some exhibit at your school's art gallery, since you're both into drawing.
4. Don't worry about the roommate. Yes, some guys are just born womanizing dicks (MSH's Scumbag Steve roommate comes to mind) but a lot of guys kind of lose their freakin' minds when they first to college and have cute girls in proximity pretty much around the clock. Though if you and Likes-To-Draw-Girl hit it off and become an item, don't hesitate to draw a line in the sand. It's not chauvinistic or sexist (imho) to "stake a claim", especially in a competitive environment like a college dorm.
5. Trust me, any perceived potential humiliation you're worried about? It's small potatoes compared to the humiliations you'll have later in life. Not trying to be a downer, but life just does that shit to people. And you'll still survive.