What are my rights as a tenant who is having issues with secondhand smoke entering my apartment on a frequent basis?

I recently moved into an apartment and the tenant below smokes excessively (almost every hour for 20-40 minutes at a time) from 4am to midnight. We shut our windows and use an AC unit to try and prevent smoke from entering the apartment but it still permeates our living space. Roommate and I have documented history of asthma and suffer headaches and nausea during the longer smoke periods. Before moving in, I had a respiratory infection, resulting in chest xray, antibiotics and advair. The smoke irritates my condition and makes breathing more difficult. I discussed this information with the manager and was told that she will not do anything and that we should have asked her about the habits of neighbors and disclosed our condition before moving in. This sounds like a violation of FHA.