Well she said "Maybe I don't know if I can" I think she's grounded.. (her parents are like Nazis so that could be it too.)
Oh dude, you're good to go. That's a "yes I'd love to because you're so hawt" with a potential condition attached, no problem. If she can't make it this time, you just play it cool and give it another try later.
And the girl gets grounded, nice. That's a good sign.
