Have you had your thyroid checked? My throat used to feel like it had something stuck in it. I also have Sjogren's Syndrome, which dries you out badly. I had a couple of episodes where I'd have an esophageal spasm and food would get stuck in my esophagus and the esophagus would spasm around it. NOT fun. Ever since Ive been on the Levothyroxine my swallowing issues have subsided. GERD can irritate your esophagus, so that would be the place to start, but if they can't attribute it to the GERD, I'd check the thyroid next.
It could very well be. My husband has GERD and often feels like he has something in his throat, and diffuclty swallowing. The acid may have created a sore spot that has swollen.