Hello,
Thanks for posting your query.

Could be either circulatory, tendon or even neuro-muscular, it is hard to say without an examination.

First you should ice it and elevate it. An aspirin to thin the blood could help as well. If this doesn't, it could indicate high blood pressure and you should consider seeing a doctor. It may indicate some sort of a blockage as well.

Long term usage or large doses of Ibuprofen could cause this in a small percentage of the population.

If your pain spreads only to thumb, you might be suffering from median nerve at the wrist in carpal tunnel. This pain often occurs during sleeping. The pain often is associated with paresthesia and tingling.

There is a simple test you can perform at home. Try to gently flex your wrist as much as possible, and wait for about 60 seconds. If numbness will occur this is very probable you have this disease. To verify it electromyography and nerve conduction velocity should be performed. It can be treated by simple surgery.

There is also a chance that you are suffering from veins thrombosis. This can also cause pain of your arm and forearm and it is always associated with swelling and redness of the area where it occurs.

Hope I have answered your query. Let me know if you have any more concerns.

Please accept my answer in case you do not have further queries.

Wishing you good health.
Regards.

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