If there is not any nose or eye discharge it is likely that it is the environment like PeppersMama metioned. Rabbits can and do have allergies and it can be caused from anything like sticking their head into the hay and inhaling dust, a nose-tickle from a strand of hay or fur itching their nose, perfumes, deoderizers, dust and pollen etc. Shake out the the hay a little before dispensing to your rabbit to help and also, when was the last time you vacuumed the cage and its surroudings? I find that Daffodil is most senstive to that and if I put off too long with the vacuum, she has a lot more sneezing fits. I’ve also got a small air purifier next to their cage because of her allergy problem.
It is definately something to keep an eye one, expecially if you don’t know the habits of your rabbit quite yet. If any discharge starts and eating or pooing stops, arrange an appointment with the vet.