Try having some water in your nose and let it drain into your mouth. You don't need to use much. Just for a try.
My experience is that the reason for the "lump in throat", is that air may be pressed down while swallowing if your eustachian tubes are dry and fails to open. When condition arise, the swallow doesn't understand that it's air coming down. It thinks it's food and start spasm.
Have a try. You may use a neti pot with the special water.
I think before you begin to spend money for health treatments, you may wish to visit an Ear, Nose, and Throat(ENT)specialist to determine whether there is a growth or swelling in your throat. It is possible that your esophagus is playing a part in your pain. You may also need to visit a Gastroenterologist who can perform procedures to examine your neck and throat sections. I once had a problem with my esophagus, and several procedures were done that viewed on a fluroscope while I swallowed liquid Barium to trace whether my throat was affected. A growing mass of tissue and swelling might feel similar to you so special tests may be done.
Good luck.
Harrald