Brief Answer:
Get a repeat MRI done; follow as advised

Detailed Answer:
Hi,
Thank you for posting your query in healthcaremagic.com
This is Dr. Swarnava dattagupta answering your query.

I understand your concern.
First of all, I need to ask few questions like-
How old are you?
What is your occupation?
Do you have to sit in a same posture for prolonged time?
Is there any history of trauma?
Since when are you having this pain, 1 year or longer?

Kindly answer me the above so that I can help you further.
Cervical spondylosis in earlier stages might present with the above symptoms. Also, chronic neck pain due to maintaining same posture for long or muscle sprain may be other possible causes. However, I would suggest you the following-

Avoid heavy weight bearing on the affected side.
Static neck exercise and shoulder range of motion exercises.
Painkillers with muscle relaxant and antacids.
A repeat MRI or atleast an Xray of cervical spine and left shoulder.

Hope i have answered your question.
Get back to me with the answers and reports.
If you have any further questions i will be happy to help.
Regards.

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Brief Answer:
Follow as advised

Detailed Answer:
Hello.
Thank you for the info.
As you are in an occupation where you have to sit in a same position for long, I would suggest you to change posture every 1.5-2 hours. It would be better if you could do the exercises in such breaks.
Alongwith, avoid sudden forward bending and heavy weight bearing.
Also, hot compression in the affected area might give you some relief.
Take painkillers- tablets if severe pain, and slowly shifting to local application of gel when it gets better.
You can continue in the above way for a couple of weeks and if the pain still persists, get an Xray or MRI done.
Also relax. Anxiety might lead to many problems. Consult a psychiatrist or psychologist if necessary.

Hope this helps.
Regards.

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