According to google, it sounds like she might have too much calcium in her diet. Try googling bladder sludge. Is she eating and drinking normal? Sleeping normal? The attitude could be from hormones since shes at the age a lot of buns start puberty. Worst comes to worst, it never hurts to go to the vet

White goop doesn’t really sound like calcium in her pee, that’d be more like a chalky residue than “goop”. Here’s a pic of normal white calcium-residue in pee and another one of bladder-sludge: http://www.medirabbit.com/EN/Uro_gen_diseases/generalities/Sludge.htm

A rabbit not eating and not taking a treat is always serious. You need to get her to eat or take her to a vet within preferably 12 hours. Bunnies must have food in their system all the time or their intestines stop moving, which is very, very dangerous. A vet can do an x-ray to see so there’s no blockage in the GI tract, and then they can give give sub Q fluids, a pain-killer, and if needed a gut motility drug.

I can’t say what the goop is, rabbits can’t vomit so it isn’t vomit.

One of my rabbit has recently been suffering with white goop in the corner of his eyes… We took Charlie to the vet and they flushed his eyes out as the tear ducts were blocked. 10 days later there were sights of to white goop so we took him to a specialist, he’s got inflammation of the nasal tear duct… He had them flushed out and is currently having anti biotic eye drops.

The specialist mention if it’s a constant issue then later on he will need x rays but that’s further down.
I hope Charlie’s experience has help you with yours.

I’m glad she’s doing well again! “Meanness” (which of course isn’t actual meaness but rather territoriality) in a 3 month old female is a sign puberty has begun, but you need to distinguish it from lashing out from pain. That she’s back to normal again is consistent with hormones though – the levels rise and fall, like in a human teenager. Monitor appetite, poop amount and poop size, those are the major things to watch, and if the goop returns, a vet check is the best idea.

Thanks for posting the MediRabbit link, Bam. Crysta experienced some chalky red sludge type stuff, but the vet took a look at my pics and said it was sediment, which looks like the normal pee pic (only more rusty in colour).

I will add that the vet said she could feel poops in Crysta’s belly, backed up, so Crysta is on Critical Care, wet greens and lots of hay. For the record, she is eating normally & poops are getting bigger, so we’ll see how it goes. It was the smaller poops that tipped me off, Quinn the dwarf, so I am glad I saw the vet sooner, because I thought it was one thing but it turned out to be another.