@Gina41 I'm not an Airbnb employee, just a host, but I can answer your questions.
1. Payments for reservations (except for reservations of 28 days or more) are charged when the reservation is confirmed. Airbnb holds onto the payment until 24 hours after check in at which time the funds are released to the host. The Guest Refund policy is such that if a guest arrives and the place is dirty, misrepresented or otherwise unacceptable, the host will not be paid and the guest will be refunded.
2. If you were to cancel your reservation, your refund would be subject to the host's cancellation policy which may vary from Flexible, Moderate or Strict. This was disclosed to you when you made your booking. Here's what they mean:
https://www.airbnb.com/home/cancellation_policies
Airbnb service fees are not refundable in the event you cancel.
The only exception is where there are Extenuating Circumstances:
https://www.airbnb.com/help/article/1320/extenuating-circumstanc3.es-policy
3. If you no longer see the listing when searching, it may be because the listing is fully booked or the host has made his place unavailable for reservations for whatever reason...might be travelling, doing repairs, etc. Do you have the listing link? It should look like this: www.airbnb.com/rooms/xxxx where the x's are numbers. I'd be happy to take a look for you.
Hope this helps! Clare