Brief Answer:
Possible muscle strain.

Detailed Answer:
Hello dear, welcome to Ask a doctor service.
I read your query and here is my advice.

I think it can be a muscle pain and weakness possibly by a sudden strain, movement, heavy lifting or fall you recently did. Possibly if you are in poor physical condition, lack of exercising and working on desk most of the time.
If possible do a x-ray of spine to see its conditions if you possibly have bulking disk, arthritis or other physical irregularities.
Taking antinflammatory drugs such advil or naproxen can help you with pain and inflammation.
Use warm and cold compresses alternating them to stimulate circulation.
Doing a bit of stretching is useful.


Hope I have answered the question.
Let me know if I can assist you further.

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