Hi @Lelle
Nerve pain is a strange beast. I've got totally explicable pain in my upper body following a thorough filleting sustained over ten years of surgery, but I have other weird stuff that had been going on for years before that.
If my bladder is full, I get a terrible ache down my right leg and, inexplicably, my ribs and shoulder. If I get cold in bed, ditto. A doctor years ago told me he thought it might be damage to my lateral femoral cutaneous nerve. What causes that? Might be tight jeans (thank you 1980's) and legs of different lengths (thank you genetics) Riding horses and motor bikes in tight jeans probably didn't help. The upper body pain, he thought, may have been referred or due to postural changes because of my crooked structure. It's never been resolved and I've learned to live with it because while it's intermittently painful, I don't view it as sinister. Just another example of bodies being imperfectly wired or structurally damaged.
If this condition predates your surgery, it's reasonable to assume the pain outside the surgical area has another cause. Maybe start asking your GP more questions once you feel up to it. If you've got a good GP, their overall assessments can be really informative.