Welcome to BB…
As a new bunny owner, you’ll soon learn that there is a very fine line between over-reacting and under-reacting. They can get sick very quickly, so it is good to be attuned to any changes in eating, pooping, or general behavior/activity level.
You did the correct thing in calling the vet, and I agree that this sounds like something that can wait until next week. Have the vet do a full introductory exam including a fecal test. It is always a good idea for a new pet to have a vet exam shortly after coming home. Hopefully, the vet you have contacted is rabbit-savvy.
In the meantime, simplify your bunny’s diet. Remove anything that isn’t hay or a plain timothy or alfalfa pellet (i.e. corn, grains, cereal pieces, crunchy bits, dehydrated veggie/fruits, fresh fruits, and any other pet store treats you may have purchased.)
Excessive cecal production is usually a sign of a diet that is too rich.
Please keep us posted on how she does this weekend, and how her vet visit goes next week.