Dougie, take it from one who knows, and has been there. Oxycontin, Oxycodone, Hydrocodone, and others are (and can be) fantastic medications. They really DO work well on actual pain.
BUT, the cells in your body adapt to them faster than nicotine from tobacco. And, if you're unawares, even when you are 'finished' with the need for the meds, and decide to stop, THAT is when the pain really starts to come out.
Simply because, you're body gets very easily DEPENDENT on the meds. I'm not saying you're addicted at this/that time, but your body is relying on its regular intake in order to function. You take away that supply, and all the sudden you're in a world of hurt that belongs in a different universe.
Only take what you need, when you need it. Then stretch it out between doses, AS WELL AS take less over time, to wean yourself off.
Because if you don't, you'll be quitting "cold turkey" and there are only two outcomes of THAT game. Pain and suffering whilst you bull your way through (with sheer dogged determination and rage) or you're a junkie that'll sell your mothers TV to get a fix from the guy on the corner.
Pick one.