Welcome in H.C.M.for query.
I have gone through your query regarding severe pain
during speaking on left side of neck and you are not getting any relief by medicine.
On the basis of your symptoms and treatment history it appears to be pain due to elongated styloid process. Because pain due to Eustachian tube obstruction is always associated with blockade in ear , heard of hearing and echo of sound. Eustachian tube dysfunction
usually herts in ear during swallowing. While on the other hand elongated styloid process usually herts during speaking and on the movement of neck.
To confirm it you can take X-Ray of mastoid in oblique view 30 degree. this elongated styloid process herts the glosopharyngeal nerve
thus gives severe neuralgic pain.
hope your query is explained.