Brief Answer:
Pinched nerve...

Detailed Answer:
Hi,

I went through the details. The pain and tingling you describe is known as paraesthesia. Sleeping in an abnormal posture causes pinched nerves and blood circulation disturbances. It results in transient tingling and pain. So if the symptoms are short lived, then I would not be concerned. You need to make sure you don't sleep in a wrong position.

However if symptoms persists for hours, you need to be evaluated further for cervical spine abnormalities.

Hope this helps. Let me know if you need clarifications.

Regards

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