Call her. If she doesn't answer, don't read too much into it, there are a whole host of reasons why she might not be able to answer at that specific time. But if she doesn't get back to you, I would say give it a couple of days and try one last time (I say this because you have stated that you like this girl). If you get nothing after this, then realistically whats the point? Just try to focus on the fact that in a few weeks, its highly likely you won't have the same desire to see her anyway.

The daft thing is, she probably does like you, but as men are (in general) more logical than women, we wonder why they stop replying, when we're sure they're interested...ever had that feeling? I remember having it when I was 17, and I remember having it last week. And I envisage having it quite a few more times in the future

Some you win, most you lose; you just gotta love it for what it is

the one piece of advise i could give, which agrees with wakes advice, is only ever text back 1 for 1. if she doesnt reply to you, dont send more messages. it looks desperate and puts a girl off you. and if it takes her two hours to reply or something, ill normally get back to her the next day, otherwise you risk looking like you were just waiting for her reply. try going out and finding someone new to text while you wait for her reply