Dont really follow you there, Jane!
Nevill got himself up from the Aga once he regained conciousness, he then phoned JB before venturing upstairs where he was shot in the face by Sheils, then he was shot in the arm and shoulder as he stumbled back to the kitchen.
Once in the kitchen , Nevill was prodded and whacked with the rifle barrel before succumbing to his injuries and tripping/falling onto the chair/scuttle before being shot in the head four times!
Oh right! The poor man has a concussion which has laid him out for three hours, but he gets up from the floor, without stumbling, as if rising from sleep, goes straight to the phone to call JB, giving no clue to that he was injured, then trots upstairs, only to be shot by Sheila. However, still suffering with concussion, he still manages to stay on his feet to get downstairs -one might reasonably have expected him to tumble- only to eventually reach the kitchen and stumble face forward into a chair which is facing him, having walked through the stairs door which was probably behind him.