You are not a bum nor a hypochondriac, and your doctors are competent. Your problems are just outside common medical knowledge, which is frustrating not just to you, but also to your doctors, so what else can they do but dismiss?
You do have a sinus infection (which may be only part of the problem), otherwise nasty balls would not be draining into your throat and causing that blocked feeling. Since you have few other symptoms of sinusitis, it may possibly be a fungal infection, which could be causing inflammation of the brain and the nerves coming out of it.
Here is the only way to get rid of undetectable sinus infections, short of surgery, especially in the upper sinuses, which are the ones that more often cause nerve problems.
http://www.medhelp.org/user_journals/show/2322
The Flip-Turn Sinus Flush is mildly risky, because you have to bend over to do it, preferably in a shower, but you can also do it outside on soft ground. And wth, you climb 14's anyway.
The sinus problems may be a symptom of something else, perhaps an inflammation of the brain and the nerves coming from it. I recommend The UltraMind Solution by Dr. Mark Hyman MD. It has a lot of science to wade through, but is also practical. Some physicians think he is a nut, but probably the same ones who think you are a nut.
He's just doing something (functional medicine) that the Chinese have known for centuries, and a practical guide to that is Asian Health Secrets by Letha Hadady, which also gives treatments for system inflammations.
Also, continue if you can to see other doctors, as you may find the one with insight into your problem.