Odd Sensation in Throat After Swallowing

For the past 12 years or so I have suffered from an odd sensation after swallowing anything more than liquid (This includes imodium (immodium) tablets which are tiny).

The sensation is a lump that starts on the right hand side of the throat, under the adam's apple, and just a little to the left of where the point of the jawbone is (The furthest point towards the throat). After a few minutes, the lump will move to the center of the throat just under the front of the adam's but still under it. It then proceeds to move to the left, about at the same position as it started on the right (Just under the point of the jawbone). It shows up after swallowing anything more than a liquid, as I said and bread type substances (Pizza crust, bread etc) seems to make it worse. The sensation is either a physical lump, or a raw spot in the throat like a sore throat.

So far, doctors have said it's either sinusitis causing a swelling in the vocal cords (Because that's when I first noticed it) to smoking related (Problem is it has been around longer than I have been smoking by a couple of years). Doctors have looked down the throat while it's been occurring, and have never seen anything stuck in the esophagus. No severe continuing heartburn though I get heartburn on a rare occasion, and it never causes me any problems in getting in air.

That last check anyone did on it, was during my last physical when the doctor checked my thyroid and simply said "It's palpable" whatever that actually means.

Any ideas of what I might want to have checked out, since the doctors who have I talked about it with have dismissed it as either sinusitis, smoking, or GERD (Which I do not have)?