Hello! I would like to answer your question.
A rabbit can have swollen eyes and a runny nose for several reasons. Tooth root abscesses and other dental problems can cause these symptoms, because the roots of the upper molars are very close to the eye and the nasal cavity. Sometimes dental problems can cause them to slobber a lot as well. More serious causes of swollen eyes include myxomatosis and pasteurella. Myxomatosis can be transmitted by biting insects, and can cause the eyes the swell as well as her genitalia and under her chin and elsewhere. Unfortunately, this disease is usually fatal. Pasteurella is a very common bacterial infection in rabbits. It is treated with antibiotics, but often takes a long time to resolve if at all due to some antibiotic resistance. Pasteurella can cause abscesses to form anywhere, including in the lungs and in the abdomen.
I'm glad you are planning on taking her to a vet tomorrow. Make sure that s/he examines her mouth well, looking back at her molars.
Do you have any other rabbits? If so, make sure to separate Mabel from the others and clean all the equipment and the hutch really well to hopefully prevent spread of disease if it isn't a dental problem. When caring for the others (if you have others), take care of them first before Mabel and then wash your hands really, really well.
I'm sorry to hear that your bunny is sick, and I hope she feels better soon! Hopefully this will be something that can be easily fixed with antibiotics or a tooth extraction. Good luck, I hope my answer helped, and if I can help further please feel free to ask!
Thank you for your advice. Unfortunately Mabel was diagnosed with having Myxomatosis and so we had to have her put to sleep. We are keeping a close eye on Bessie, our other rabbit, who shared the same hutch and run as Mabel as we have been told to expect Bessie to show symptoms some time in the future.
I have 3 very upset children as both rabbits are beloved pets.
Thank you again for your help