I can understand that you might feel quite confused at times. But in those moments, try to be more observant and ask yourself, that are you actually mistaking her friendly affection as a gesture of being into you? Is this something that maybe she says or can say to any of her good friends as well, as a general gesture of being courteous? And still if you are not able to get a clarity, best way to figure it out can be- to let her know what you are feeling and ask her version of it.
You can give it a try!
And regarding your second dilemma as well- I understand that maybe you feel scared that what if speaking about your feelings jeopardize your chances, right? I know it is easier said than done, but there is no harm in letting the other person know what you feel about them, yea? The end result is not in our hand. But if you really feel for her, maybe try to express that at least, and leave the rest in her hand.
Hope it helps.. Good luck!