Good luck with your visit! I would try not to worry too much, if you can help it. Who knows what will happen when you meet? One or both of you may find that you prefer to keep things platonic vs. romantic. Maybe it would be helpful to tell her now that you'd rather the first visit be platonic, to lower the stress levels? You could always change your mind when she gets here
It does sound like things are moving at a whirlwind pace which probably makes it scarier.