First of all. How old are you? Highschool, college or older? Because that's a factor for the reaction.
As for the advice.... God, why did I'm giving love advice? ive never been in a relationship before myself. But, according to my romance book and day to day observation. Let's maybe try to find out about her feelings about you, like you are a best friend right? That's something, or maybe try to ask some of your mutual friends, preferably girls since they usually know, gossip and all. Or, if you are not dense like 99% of the male population, try to look at her reaction yourself, you know subtle things like extended physical contact, shy smile from here. Anything really! And if you sure you get all the sign, go confess to her. Do it, really because if you do like her, the last thing you want is someone to try to 'steal' her from you due to your own lack action. In shorts.... Man up! Tell her and don't afraid of rejection. Think positively and make us proud son! Go get them tiger!