you definitely did do well and you should really never come out thinking you did bad, just how you can improve.

Now when you were with her it sounds as if you werent paying attention to her IOIs otherwise i guess you wouldnt be asking. when she first agreed to dance she expressed interest similarly with when she asked you to go outside, unless there was something you could think that made her want to stop dancing and leave, but dont think about that. When you grabbed her as you went in this small form of kino i believe would have done wonders, however if what you were saying wasnt right and it was a awkward grab well then no. But with the grab and the statement lets just pretend to be partners could have been too much butt read her body language. did she tense up or did she move closer, things like that. i think you should have incorporated a little bit of humour in with that line as well as it would have added a nice flow to things. to finish up with determining if she was interested or not would have been when she called you over with her hand as a girl who is not interested would not do that unless she was using you but i ruled that out when she asked to share a cab as im sure there would have been many other people to do that.
with did she just want to fuck you mmm maybe but really is that a bad thing? you can use it completely to your advantage as you can tease her as not only have you succeeded in her expressing interest in you but also have her hormones wrapped around your finger. dont tease too much as "no body likes a tease" use it in moderation

i think you definitely should add her on facebook however dont say anything to lead her to believe your keen and want her as that will give you the most un appealing characteristic of desperate, say something to her like "hey, this is the girl i met last night right?" wait for reply.. then say something like "ah awesome i have been looking all over for you." (build her excitement and curiosity) then drop something completely not what she thinks "yer, i have been asking everyone but did you manage to see my wallet at all? i think ive lost it." that way she gets lead on then pushed back. a kind of quick verson of push pull.
hey im only new to this site but this is all i can offer.
