Repeat upper endoscopy may be of benefit. Alternatively, consider fluoroscopic esophagram.
Hello and welcome to the forum. Thank you for your question but sorry you are having this issue. That has to be frustrating. Often endoscopy is performed under 'twilight sleep' or very light anesthesia and they give you something additional to relax you prior to starting it. Did you have a bad experience under anesthesia last time to create this fear? Truly, endoscopy is the best way to see exactly what is happening. However, your symptoms sound like that of GERD which involves the esophagus. Remember that your esophagus is the tube at the back of your throat so very intertwined. Normally, a doctor can go ahead and treat based on these symptoms with that assumption. Have you been offered any treatment? What are your doctors suggesting?
This article has ways to diagnose and does include some other ways than endoscopy, however, that is really the best way. It also has ways to treat to consider. https://www.mayoclinic.org/diseases-conditions/gerd/diagnosis-treatment/drc-20361959
Hello and welcome to the forum. Thanks for your question but sorry about your symptoms. Typically for an endoscopy, anesthesia is "twilight sleep" anesthesia or light anesthesia. Often you can have something to relax you as well before the anesthesia starts. Did you have a bad experience last time making you afraid to repeat anesthesia? Truly, endoscopy is the only way to really know for sure what the issue is exactly. What you describe does sound like GERD and that is going to involve the esophagus. Treatment should begin for GERD if it hasn't already. Often, they can try to remedy the situation based on symptoms. What are they suggesting?