Pre-op Pain VS. Post-op Pain

I'm having surgery to repair a medium-sized tear at the end of March. The only pain I feel on a daily basis is when I lie on my back. The pain radiates down my arm and into my neck and back. It is particularly bad in the elbow.

I've taken a couple of naps in the recliner to get used to it and find out what I'll need to be comfortable, but no matter what I do, after about 10 minutes the pain is almost unbearable. I'm able to sleep in bed on my (good) side with no problem, but I know that isn't recommended during recovery.

So my question is, should I expect to have this same issue post-surgery? Or will the pain/discomfort from the surgery be different than the pain from the injured tendon?

Hope this makes sense. Thanks