Send her a picture of your penis. That'll show her!
In all seriousness though, I would try to bounce back from it. Maybe she's shy and wants to take it slow and so when you show up and the hang out is fuck awesome she THEN see's you as more of romantic spark.
I mean up to now has there been flirty talk? Remember at some point you have to say some sorta shit that isn't just friend material in a text or a phone call. Whether that's a compliment on her looks somehow, or turn it around on her, an example would be like:
She texts you what you are up to, you say, " Just got out of the shower. Yes yes I know, Nakey A human Becoming. Quit day dreaming ya perv!...also your hiding spot in the bushes wasn't very discrete. I'm on to you! "
^ Something like that is flirty, not friendish, but not over the line to be taken as woah creeper/sex fiend.
Has there been any flirty chat between you though? If there has, then you need a recovery text like, "Platonic? Well of course. I'm not some cheap floozy you can just take home. You have to buy me a drink first at least!

"
That's a decent recovery text. Go there, wow her with your awesomeness, and if at the end she only still see's you as friend material? Oh well. A night out with a good looking girl, some food in your stomach, and hell maybe a friend worth having, or at the least, experience on dates for future girls off OKC.