I am EXTREMELY congested, but when i blow my nose nothing comes out. What should I do?

Every time I become sick, nasal congestion follows. Right now, I am getting over a sore throat and I am extremely congested. Usually this can last up to two weeks after my original illness, depending on what I do to treat it. Ive tried everything from vicks, to steaming pot of water, to practically every kind of decongestant I've come across, to chicken soup, tea, drinking lots of water, maging my sinus pressure areas, and nothing seems to help even the slightest. The ONLY thing that gives me immediate relief is Sinex nasal spray. It literally gives me 12 hours of relief every time I use it. However, If i use it for more than a couple of days, it makes me more congested than I was in the first place and seems to just bring my congestion back. (I had to learn this the hard way when I found myself using the nasal spray for about 3 weeks and when I ran out and went cold turkey for a day my congestion went away on its own) Anyway, I'd like to not use nasal spray at all this time but somehow get some fast relief. Any suggestions?