With that additional description, I strongly urge you to undergo treatment for the LPR form of acid reflux. The worst that can happen is that the meds don't work and you move on. LPR does not require a lot of fancy tests. Most doctors (who know about the condition) consider a positive response to the medication a diagnosis (albeit indirect) in itself. And all you need to do is take 2 doses of a PPI every day. But there are 4 PPIs on the market, and you may need to experiment to find the one that works best for you. I recommend trying them in this order: Nexium, Aciphex, Prevacid, Protonix. I also recommend taking the pills together first thing in the morning.
It would be helpful visiting an ENT, because an ENT can scope your throat and tell you if you have any redness or swelling on or near your larynx. Laryngeal redness and swelling is a telltale sign of LPR. This is an in-office procedure that doesn't hurt, and only requires that you inhale a numbing spray.
I understand that you did the GI scopes and that you don't have GERD. If you had the GERD form of acid reflux, you would likely have damage in your esophogous. But LPR damage is typically localized in the larygeal and pharyngeal areas. We don't really know why yet, other than theorizing that the upper esophageal spinchter has pooped out and is letting acid into the throat. LPR damage is literally a higher level of damage, and GERD damage occurs lower down in the esophogous.
I suspect that your feeling of needing to yak has something to do with weakness in the upper esophageal spinchter area.
You don't need to visit an ENT in order to get a prescription for a double dose of a PPI. Even your PCP can prescribe a double dose for you, or give you free samples.
Usually, if it isn't true sinusitis, and it isn't true asthma, it all comes down to acid reflux, which can give you symptoms of both, but not respond to treatments for either.
It's a horrible condition that destroys lives without treatment, something that the medical community is finally waking up to. It is devastating, and interferes with a person's entire quality of life.