The upper endoscopy, which I assume was done, would rule out many of the major upper digestive disorders that can lead to these symptoms.
Obtaining more specialized tests, like a 24-hr pH study and esophageal motility studies - looking for GERD and motility disorders respectively - can also be considered.
If negative, there may not be a discrete GI disease present that can explain the symptoms.
Appropriate treatment of the Barrett's esophagus is crucial, as this can lead to esophageal cancer if not appropriately addressed.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.