I am Doctor Thomas, a double board certified doctor in internal medicine and integrative medicine, with advanced training in several other fields. I am a clinician of over 20 years experience. I will give you an initial answer or ask you a question, but be sure to use reply to expert to communicate with me as needed.
Hopefully the camera was put into your esophagus.
You could have acid reflux causing this.
The only way to tell for sure is PH monitoring of the esophgus with special equipment to see if you have acid coming up. It does not wound like this was done.
Another possibility is disc disease in the cervical spine, the neck. This can cause a sore neck and a painful throat, if it is severe enough.
Infection they would have seen.
I suggest that you see a gastroenterologist if all you saw was an ear nose and throat doctor, for PH monitoring.
Spasm of the neck muscles and vocal cords is also possible
This possibility should also be discussed with your doctors.
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