I don't know man. Your first response was great but the second part.. I'm an old vet in the dating scene and it is still possible in that circumstance. Maybe shit really did come up. Maybe shes seeing other dudes (who cares shes not your gf yet) or maybe its something you and I can't think of.

I remember when I was 18(I'm 32 now) and a girl flaked on me a lot. Wasn't because she was rude... she just had strict parents who controlled her life at 18 and didn't want to tell me that.

Its probably not that but it might be anything. I'd still message her from time to time to let her know you're still interested and that being flaked on doesn't bother you. Its just a text anyway.