Since this is only occurring at night. Somewhere there is a pinched nerve that is being compressed and/or not getting enough circulation. I would however see your doctor for further evaluation. Generally a NCV and/or EMG test can indicate where this nerve is occurring. Then you can get proper treatment. If left untreated could cause further damage and may even start to happen during the day as well.
It may be the mattress you are sleeping on or the pillow you are using that could cause this too.
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