Generally numbness indicates a pinched or entrapped nerve. Since this is generally in the A.M. then it appears that the way you are sleeping is pinching on a nerve which may be due to the hard bed as well. You can try a different sleeping position to see if this will help. Also you can determine through a nerve test if this is just the start of being an entrapped nerve as well. But since it' s not all day at this point, it points to sleep position/bed.
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