Welcome! Rabbits are very sensitive to perfumes, cleaners and other toxic substances, and exposure to any of these would be especially harmful to a rabbit’s delicate respiratory system in a tightly confined area like dorm rooms are. I would air out the room and discontinue using any perfume in it. It would be best not to use any perfumes but if you’re set on using it, wait til you’re in the hall or in an outside bathroom to put it on and wash it off before going near the bunny. If he has a respiratory infection which it sounds is likely, treatment from a rabbit-savvy vet can clear up the infection and then his nasal symptoms should clear up as well. But it can’t hurt and can only help for your bunny not to be exposed to any perfumes, room deodorizers, cleaning agents or other toxic substances as they’re very harmful to him. Glad you came to the forum and hope this helps. Good luck and hope your bunny gets better soon!