it is unfair for you to have your nuts in her hands, sitting on the edge of your seat wasting your time wondering if she will be available. she is probably too much in control.
that is bs dude, so wait.... if she can't hang out, she WON'T call you and will leave you hanging even more? either say today doesn't work out after all and reschedule, or wait for her to come to you. just don't let her walk all over you. you don't want to be the guy that says something like "ok, thats fine. whenever you are ready for me... i'm your b!tch".