Did you not read:
I'm horribly inexperienced with girls
So just talk to her about you being horribly inexperienced and all the stuff that comes from it and things should clear up.
I did, I did.
At any rate, if you're sick and can't ask her out right now, maybe you should call her to do so. Or else somebody else might take their chance
If you just had surgery, maybe you can even ride up to the school in a wheelchair and promise her you'll be walking when the date-thingie comes up. And ask her out in the same time. Brucewillisish injuries can be sexy, if you pull it off just right
Also, if you can stomach rejection just fine, there is basically nothing that can go wrong when it comes to flirting. For every perfect guy there is one girl that just doesnt want to be talked to right now/is stuck up/whatever. So no matter how good you get, you'll get rejected ever so often. So just dont care about it and have fun, I'd say.
Oh btw... I too read signals like a blind man, still. I'm not into signals, I basically force myself to ignore them, at times. I'm straightforward, I tell women what I want/need. I freak a lot of them out that way, but I dont care (well I do, sometimes
but I still wouldnt want to have it otherwise). In my personal experience, women that need to play games and cannot communicate their needs have a high rate of batshit insanity, insecurity and are generally uninspired in bed. Of course, not all of them, but more than the "I can communicate using language"-types. I had my share of playing games and signalling when I was a teenager, I'm done.
edit: on the contrary, non verbal communication, or signalling as a whole, can be hella sexy
For instance, a girl that is "wiggling her tail" at you when walking off, makin you ask yourself whether or not she is aware that she... rawr... where was I?