Welcome to Healing Well! At 12 days post op, your insides are in the process of healing. In addition, there could be residual gas (pumped into your body to make it easier to view the surgical field) floating around that could cause pain in
locations other than the shoulder.
Sitting up longer than usual could certainly stress your healing insides.
That said, I'm not a doctor, and a call to your surgeon's office would be in order.
I hope you're feeling better after some rest.
Let us know how you do and what you find out!
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