Is it normal i think she likes me?

at the gym I go to often, there is a very cute girl who works at the front desk. She has long dark brown hair and wears hoodies a lot. I like her sense of style and she seems cool. My only complaint is that she wears too much eyeliner, personally I believe she would look much better with her natural eyes. I think she's in high school but I never asked. I am 26 but I look younger so she might think that I'm around her age. There is a scanner at the front desk that everyone has to swipe their membership cards on, and usually she hangs out near there. I've noticed that whenever I swipe my card she tends to either look at me or say something to me. For instance today as I was trying to get the scanner to read my card, she was standing nearby. I was pretending not to notice her but she glanced in my direction and said "hi" and "have a good workout". Her tone was sweet and gentle. She also often seems to watch me as I'm leaving the gym and says good night. Now maybe I'm just being paranoid but she never seems to be this nice to anyone else. I'm normally not shy but something about this girl makes me feel self conscious and nervous. But I strangely enjoy those feelings and don't want it to stop. Until now, most of our interactions have been awkward with her initiating the talking and me just sort of smiling back at her in a friendly way. But if she really is interested in me, which I still have doubts about, then I would like to return the favor. And I would also make more of an effort to impress her. I just don't want to act on a wrong impulse. Maybe I should start by actually getting to know her and vice versa, because right now we're basically judging by appearances. She might turn out to be different from what I expected, and that's normal. The reason that this is so difficult for me and why I'm perhaps over-analyzing the situation is because never has a girl shown interest in me, so I don't know how to respond. It's always been the other way around and often met with failure. The last thing I want to do is project my own insecurities on to her. Even if it doesn't work out I want to feel like it wasn't due to me being a complete social retard.