She might still be a little young for a spay. Regardless of that, she does need a vet. A good one with rabbit experience. I understand that you as a minor have to follow your parents guidance but your mom’s responsibility as the technical owner of the pet should understand that rabbits are not pocket pets. They need the same amount of attention, space, and health screenings as a dog or cat, if not more. The only difference is that a rabbit can’t make noise to say they’re hungry, in pain, unhappy, etc like a dog or cat can. A checkup at an exotics for a rabbit is usually cheaper than or same price as a dogs check-up. At least for me where I live. Maybe you should do some research for some in your area and visit rabbit.org to explain the health risks of bunnies, especially the cancer risks for un-spayed female bunnies to your mom. My parents always responded well when I did research and approached them maturely about subjects like this.