Need Advice on a Shy Girl?

I'm really confused about this situation. I met this girl back in October while volunteering at a festival, and we talked for a bit while working, but haven't really talked sense. After talking to her a few times after cl one week, she suggested that we meet up some time after cl so that we have more time to talk. We did, and we ended up talking for around 3 and a half hours before she realized she was late for a meeting and had to run. Yesterday, for the first time ever she left her seat before cl and came to talk to me about her night, how bad it had been, how she had gotten no sleep at all, how she was going to see the New Moon movie that night, etc. I want to ask her out, but... I'm just not sure if I should, or if she is even interested. She seems to not necessarily be shy, which I originally thought, but just so pure and moralistic that most college-age people seem to avoid her. She doesn't believe in before marriage or drinking or smoking or anything along those lines, so I think it has made her a bit of an outcast. At the same time, she has never had a boyfriend before. This is two-fold, in that when we had lunch together, she seemed to talk only about herself, never asking any questions about me or my life. Which is again twofold, because the conversation flowed easily without having to ask questions about interests. Also, she had had a lot of caffeine during lunch, which she says make her hyper, so it may have been due to that. I bought her a cup of hot cocoa the other morning as a surprise, but she turned it down, because she just so happened to have one already that she had bought. I'm just not sure if I should ask her out... I don't know, it might be too early to ask... maybe I should wait. But at the same time, I want to make my intentions clear before Christmas Break. But again, at the same time, I don't know if she even likes me at all. But then I think my chances are probably really good due to the fact that she has never dated before. She's so sweet.... so amazing to be around... and I don't think she has a clue how I feel, or even how much I appreciate her morals and values. Geez, I just don't have a clue and I'm completely at the end of my rope and the last of my hair on this one. Any ideas/advice?