What could be wrong with my central air unit?

Two days ago my HVAC system was sounding very loud. It is located inside of my apartment. Well, today when I woke up I smelled this horrible odor, it almost smelled like chlorine, but a little different. It is nothing I have ever smelled in my apartment before and I have lived here for a long time. I tried calling my landlord before I went to work, but he was not in. So I turned off my ac when I left for work. I just got home like twenty minutes ago and I turned it on and now it doesn't seem to be working at all. The unit inside my apartment sounds like it is running, but no air and I mean no air at all is coming out of any of my vent things that are in the ceiling.... what could be wrong with it? Could that horrible smell be from when the ac unit was on over night? I can smell the chlorine smell still but it is very faint, I have my windows open now and my patio door to air out my place too...