I thought I might be able to help put your mind at rest, however I, like you (maybe), am a worrier so I still think you should think about a second opinion.
I suffer from acid, and occassionally reflux acid. I have suffered for ages with this and again I, like you, worried about this lump in my throat, but I have found by experience that an irritation to the gullet in any form (and I get irritation right down at the bottom where the gullet joins the stomach) I get a feeling like alump in my throat.
Also remember that if you get upset about this the old saying 'I got a lump in my throat' is true because it's a reaction by your body that produces an irritation which causes the feeling.
Hope this helps and it isn't too confusing.
All the best