Hi, I have gone through your question and understand your concern. You need rest for some period till all your surgical wound heals and muscles get repaired which will take around three weeks to three months. Hanging heavy weapon on shoulder again can be dangerous. You can take it on the other shoulder. Try some physiotherapy exercises afterwards to regain flexibility. take meal rich in vitamin c like lemon, fresh fruits which increases healing. Take care of your body position while you sit or sleep.