I fancy a girl, but I dont know if she fancies me back?

Well, the title itself gives away the basis of what I want to ask, so I'll break down the situation so people are able to decode it.

Basically, I'm a first year drama student studying in London. I met this girl during a social event the school of drama within my Uni throws to get the first year drama students to bond and get to know each other. We got along, laughed, joked, talked, all that jazz. Next thing I know we are in the same seminar classes as each other. This helped build a more solid social relationship with this girl. It was at this point that I started developing feelings for this girl. In seminar and on Facebook, we would constantly "abuse" the other, playfully trying to get reactions out of the other. At times in seminar she would start touching my hair trying to "get something out of it" or because "a piece of hair was sticking up" She even created a pet nickname which stuck to me to glue, to the point others began using it too, becoming a sort of "in" joke. Likewise I got her a white bed sheet as a reference to an "in" joke she was the punch line of.

When we were put in the same group for a practical assessment, the social aspect became more private and personal in its subject matter. She would start talking to me about drunken one night stands, or a boy who said fancied her, but she did not like back. The boy in question was someone who I saw as competition for the girl, and she did not hide her feelings towards the boy, especially when she found out my dislike for the boy ( for other reasons besides potential competition). Likewise during extra rehearsal sessions during the weekend, she would ring me on the assumption I was the first to arrive, to ask me to open the doors as they were often locked. This feels odd when seen in the context of why ring me up, if the doors are all locked, then how would I be able to find my way in. It was sheer luck rather than anything else whether someone got in or not.

During a post show party, the girl decided to have an early night, despite the protests of the rest of the group to come and drink till the early hours. When it came to the end of sememster, and people going their seperate ways, I found on Facebook she had messaged me asking for help with a written assignment explaining our performance. Likewise, she would often strip down to a sleevless top within the studio spaces we were using. Anyone who has ever worked in a rehearsal studio would know, they are very often (as was the case with ours), very cold.I found this most strange, not least because of her intelligence, but because the performance concept was her her brain-child. I private messaged her on Facebook. After helping her, she started to first, in caps start talking about how stressed she was, and thanks for listening to her. We then had a short conversation about friends coming back from uni, and how it would be nice to meet up and go to the pub with them. There was an excessive amount of emoticons on both sides of the converstaion. She ended up by the general hope you have a good break etc, and threw in a kiss.

Around this time, she started deleting messages on Twitter about other boys. My friends likewise, egging on to the fact I fancied her, thought it would be funny to frape me, and make me like random photos of her, trying to force me to bring the isssue to the surface. I gave a semi-plausable scenario, and we both laughed it off. Since then neither one of us has contacted the other, mainly due to wanting to give the other one space. The issue I have is that although I fancy her, I'm scared to play my hand as it might compromise the friendship we already have. Likewise, I don't won't to sit there if she does fancy me, watching her attraction to me expire as another guy who is alot quicker to act jumps in.