I'm not sure if she likes me?

There's this girl in my class that I really like.
One time I got into class I forgot to greet her and a classmate, and only greeted my friends and another girl, and the instant I passed the door, she said to me that I didn't greet her, so I turned back and greeted her and she felt happy afterwards. Also recently she got her nails done and my friend noticed them so he took her hand and started checking her nails out, but during all that time her head was turned away from him. The next day when I noticed her nails, she asked me for my opinion on them and then she gave me her hand and held mine tight when I was looking at her nails and seemed to be happy after I complimented her. Same goes to when I noticed her hair. I am highly sure what I just said can be very friendly behavior, but what I'm asking is that why would she care if I would greet her or not (since not many people in my class really care if I do that, also Its not that I'm a close friend of hers for her to care whether I greet her or not)
I'm not sure if she likes me?
Post Opinion