Post a message with the details, including who it is, here (if it is San Francisco, otherwise in the city forum where it happened.

Then, write a rip-off review.

TER exists to provide information about the good AND the bad.

If the lady is well reviewed and an otherwise reputable independent, it might be prudent to give her a reasonable opportunity - perhaps a few days - to contact you and make amends.  It's the courteous thing to do.  

Escorts are no different from you and me, and they can be visited by surprises and misfortune - accidents, illnesses, unexpectaed emergencies, a death in the family, and so on. She may even have been busted - after all, her occupation does have an element of risk to it!   If something has gone wrong for her, then you'll likely hear from her soon enough.

Certainly you should act at some point, but don't necessarily act in haste.

what he said above. However, give her a full 24 hours or maybe even a bit more time to get back to you. If she is a well reviewed provider especially, it's not likely that she would take the chance of tarnishing her rep for some hundreds of dollars when she could be losing thousands by this incident. Providers are real people too and she could have actually had an emergency, fallen sick, or had a tragedy in the family. You never can tell.

If she is well reviewed, chances are that she will get back to you with an excuse and want to set a date at another time or return your money to you. Just wait a little.