I woke up in the middle of the night with a sharp pain in my back leg. pain went away after 10 minutes now the pain is back but it's my whole leg now?

Nerve or Vascular: Question is whether this is chronic or just an incident. The description of "sharp" pain while laying down may be related to position and the result of a nerve compression. However, another considering is that this could be vascular related the result of a clot and/or restriction of blood flow. Talk to your primary care physician either way, but if chronic, consider urgent care/er.