I'm surgery on my big toe right foot. why is that when it's elevated it doesn't hurt as much and as soon as i stand up to move its hurts bad?

Blood flow...: When you stand up the blood rushes back to your feet and causes the pain. This should go away rapidly as the healing process continues.

Swelling: Most common cause of pain that increases with weight bearing and feels better when elevated has to do with swelling. Elevation decreases swelling and improves venous return from the operated toe. Standing decreases the venous return and causes swelling.