WRT your first point, it is not clear to me what you are doing.
If you are contacting an escort through an AW email (or similar), then you should get a response within a couple of days. It is worth checking if she has logged on in that period, and if not then she might have just be away and a bit more leeway could be allowed (although it is not absolutely necessary for an escort to log on to read messages). That is plenty of time for anyone to check their diary, read any feedback you might have and do a safety check on your phone number if you have supplied it. If you are making contact through text, then you should get a reply pretty quickly, that after all is the point of asking for text comms, especially if she is "available today" and so clearly at work.
However, if you are making contact through the AW "booking request" system without any prior contact, then just stop. Many escorts find this very annoying and you will just be ignored. Make contact through email, text of phonecall to arrange booking, and then do a booking request if required. (Of course, this doesn't apply if the escort states that the booking request form is her preferred method of contact, but this is not common).