Thanks for posting your query.
Let me know your blood sugar status both fasting and postprandial.
With the available described symptoms, there appears to be possibility of diabetic neuropathy
or cervical spondylitis
Uncontrolled blood sugar may be associated with multiple complications involving almost all organs of human body..
As such Metformin is not associated with any type of pain .
You should consult with internal medicine specialist/ neurologist
and should go for thorough neurological check up.
There may be loss or decreased biceps reflexes/ triceps jerk in upper limb.
Clinical examinations is mandatory.
You should take epalrestat, methylcobalamin
, gabapentin or pregabalin
for relief of your pain.
You should also apply soft collar and consult with physiotherapist for better relief.
Dr. Mayank Bhargava