I have a broken radius and ulna on my right arm, under cast 1 week ago, how will i know if it is healing? if i feel minimal pain when i move.

Minimal pain is OK.: But increasing pain, bluish discoloration and impaired movement, numbness and tingling of fingers suggest too tight placement of the cast. In 6-8 weeks your dr will repeat xray to determine if alignment of the fracture and callus (new bones) around the fracture site have occurred and these are signs of healing. http://www.noelhenley.com/249/how-do-i-know-my-broken-bone-is-healed/.