To be honest, I would not feel.too aggrieved in your spot. For the sake of your self-esteem I would not put too much weight on the age thing.
It is possible she was worried about age, and it is possible she double-booked, but lots of the time it will be something else. The majority of girls are quite good about answering messages, and the best escorts are great at it, but many are terrible - it is just one of the hazards of trying to see so.eone new.
If I get cancelled I just move on. If they are polite and apologetic I may try another day, if not there are a lot of wonderful escorts out there.