My advice would include about ten thousand rounds of dry firing, without a single round of live ammo. Get your gourd wrapped up in the idea of trigger control not pain avoidance. Shooting should become dry firing with noise, instead of pain with noise. You should be so sick and tired of that action that dry firing makes you want to watch Oprah reruns. Go to the range shoot a round out of the shotgun, then pick up a .22 and practice with that. Once a gun is physically sighted in it shoudn't matter if you shoot it a bunch or a similar one.
Trigger control at home, sight picture and alignment at the range ... with a .22.