Why did she hug me? Does she like me or did she think I was someone else? (it's long)?

Yesterday I was walking to cl as I normaly do every day. I'm kind of quiet and for some reason people seem to think I'm sad or upset any time I space out (I get lost in thought often). Anyway I was walking down the hall alone, there were one or two other people in that hall, but that was it. I heard some quiet footsteps and as soon as I stopped to see who was running down the hall someone wrapped their arms around me while flying foward. I stumbled and almost fell over, but regained my balance. Whoever was holding onto me tightned their arms and snuggled their head against my neck. After a minute they let go and backed away. I turned around and saw that it was a girl that I've seen around school a bit, but we hadn't said more then 4 words to eachother before. I asked what that was for and she paused for a minute and said "you uhh... You looked kind of like you needed a hug.". Then she smiled and ran off before I could say anything else. I don't know a whole lot about her, but from what I've been told and what I've seen her do she is kind of shy and doesn't have many friends. She seems like the last person who would hug-tackle a random guy in the halls, especialy somebody who she hasn't even really spoken to. We seem to have a bit in common: we are both shy, we both don't have many friends, we both love computers, and other things like that. What do you guys (and girls) think? Does she like me (as encouraged by the fact that she paused and stuttered a bit after she hugged me as well as the fact that she hugged so tightly and snuggled her head against my neck), or did I really just look like I needed a hug? I was walking with one hand in my pocket and the other holding my books like I normaly do. Oh, and is there a chance that she might have thought I was someone else? My back was turned to her until after the hug so that seems like a possibility to me, and that would explain her nervousness and the coming up with the "you look like you needed a hug" excuse.