I'd certainly suggest you see a physical therapist, such as a Chiropractor or Physiotherapist to identify the underlying cause.
Chiropractors manipulate the joints, physiotherapists release the muscles in the area. Either will address posture and other physical imbalance that might explain why your pain is persistent.
A lot of pain is "referred", meaning it’s felt somewhere beyond the source of the pain. Because of the direction the nerves run, a neck injury is often felt in the shoulder and arm, as might be the case here.
As for the meantime, you should experience some relief if you apply a combination of Atrogel®: externally and Atrosan®: internally. Neither remedy will conflict with medication but the Atrosan® can't be taken if you're pregnant.
Do you have questions? Please feel free to ask.
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