Firstly and most importantly, how long did you keep the apart after Voldemort was neutered ? Male bunnies actually retain sperm for 4-5 weeks after surgery.

Yep, that’s what I was told. Never actually saw Piglet do the deed but the second litter arrived just before Xmas. It only takes a second. Piglet was actually neutered about two weeks before the first oops litter arrive, he must have been feeling amorous about a week after Pepper brought the babies into the word as the time line indicates it was about 3-3.5 weeks after his neuter.

Roberta is right, you could end up with a surprise litter on your hands! This would be especially bad if she has a head tilt issue going on. They should be kept completely separate until 6 weeks post-neuter. Even having them in adjoining pens/cages can be an issue because they can mate through the bars if there isn’t a gap between them.

That being said, if Bellatrix is trying to hump Voldemort then it may have nothing to do with hormones and everything to do with dominance. That’s really the only reason girl bunnies hump (although hormones could cause them to power trip, so to speak). So even after she is spayed and healed and you’re officially starting the bonding process, you will likely still see humping on her part if she feels she is supposed to be top bun in the relationship.

Was it the vet that told you or the receptionist ? When it happened to me I even checked on line and got the same info from some reputable site, “2 weeks”. Wish I had found Binky Bunny first in those days, they came to my rescue when I realised Pepper had another oopsie on the way.
Depending on when it ay have happened and the stage the treatment is at for Bellatrix an emergency spay might be possible. Failing that keep your fingers crossed and make sure she is getting a diet rich in good greens with a high vit E content and try to ensure all her food is good, no pellet mixes with seeds etc (try and get Oxbow if you can) plenty of good quality hay so that you can really build up her immune system and maintain a healthy gut. If the worst has happened you will know in about a month.

Sadly vet techs and Receptionists don’t always have all the info….Their diet sounds perfect… Keeping my fingers crossed for you on the oops.
With the other behavior Bell could just be showing Volde who is the boss and the extra hormones about from his neuter could be making her a little more dominant. Give the extra few weeks and try again slowly, there is nealy always a little bit of humping to sort out who is the alpha bun.