*sigh*
Are you sure you cancelled because you were tired?
Or can you face the fact that you were scared, petrified, worried, or whatever, and dodged her?
Sleep tomorrow night, man.
You can't even reach her, man. She thinks you're a liar now. Ah God, did you ever think of, "I really would love to, how about tomorrow night, I have work at 330? If that's not cool I'll come over now, but it would be a lot easier"
Something along those lines.