im a guy and in your perspective, what do you do when a girl doesnt reply to you?
wait 24 hours and try again LOL. if she never replies at all, here's a little trick: use a number unknown to her and text her her name (example: "Viv!") and see if she replies (most probably asking "who's this?"). if that happens, chances are she's ignoring you completely and you wouldn't wanna be with a girl like that, would you?