Sorry, but this is not normal for a rabbit, and I think you need to take him to the vet. It sounds like a cold or illness, not an allergy. Bunnies do not tend to be allergic to dust and hays because that is their natural surrounding in the wild (dirt, underground, grasses, fields, etc.) so it may have been mentioned here on occasion but overall it’s not common. A cold or infection is.
This is a tough time around the holidays for an added expense, so ask your vet if you can set up a billing arrangement. She may be open to sending it in January, or taking partial payment now and the rest next month. Also, if you get into a bigger expense for something this month, many credit unions (mine does) have a “holiday loan” which is a very small loan to cover short term expenses that you can pay back next year. Check it out, if you are tighter than usual. You should try to budget for bunny expenses regularly because this will come up. (I know – I have borrowed from my savings for bunny/car emergencies, but I try to pay myself back, too.)