Mind boggling inferno of agony for one person is a walk in the park for another, and then it switches the next day. Pain amplifiers suck, and we generate them all the time as part of our survival mechanism. Current shearing physical damage pain turns into dull roars of heatbeat reflections, ie: STOP FUCKING MOVING YOU ARE MAKING IT WORSE!
So given that, I don't pretend to feel your pain. In all my years of whining, I've never experienced a ruptured disk or anything close in that area of the body.
On the other hand, my empathy level kicked enough on reading this it took a lot of wincing before I could type. Ah, empathy, the reverse placebo.
Well, you know my feeling on narcs VS others, and hope your situation allows for some real non-addictive relief.
Go find some relaxing music and ignore the world for a couple of days.
As far as op now or op later:
What is the possibility you won't have the insurance to cover the op later?
Yeah, sucks that this type of thing might be considered as part of the decision process, but if the situation is shaky, use the insurance and get it out of the way (assuming the risk rate is worth it to you).