When I suspect one of my rabbits has belly problems, the first thing I do is make them move, or give them gentle belly massages to get things going. Usually I put the whole rabbit on my leg facing me, balancing my foot on the palm, and rocking it. It becomes obvious pretty quick if it feels good to the rabbit. Repeat that hourly for 5-10 minutes.
Offer everything she is used to, you can also offer safe greens like narrowleaf plantain or leafs from apple trees, roses, bramble, even if she's not used to greens.
You can syringe feed her some water, and mix some Simethicone (Infant gas relief drops) in, about 20mg min. every 3-4 hours.
I would see if there's a way to see a vet asap too, even if it's not your usual one.
If she's stopped pooping, this is an emergency. Don't force feed anything. If she has a blockage, it will only make it worse.
Absolutely agree that you need to find another vet that will see her today. A rabbit savvy vet will understand that one cannot wait with a situation like this. It is considered an emergency! Start calling around.
The followingis a combination ofthe House Rabbit Society list for Rabbit Veterinarians in Illinois (listed at: http://www.bhrabbitrescue.org/vet.html);the Petbunny listserver member recommendations at: http://homepage.mac.com/mattocks/morfz/Vet_AZ.html; the Association of Exotic Animal...