Surgery

So I am having surgery soon, I have cancer. The surgeon said to keep taking my subs. They will give me pain meds afterwards to add to the Suboxone I think just a few days worth I’m not sure. I’m just worried about precipitated withdrawal. Can I really just add the pain meds and be fine. I’m worried about Anastasia too. I am already hard to sedate. I woke up in the middle of a surgery before I was on subs. So I need more medicine even not on subs to knock my ass out. I have been told I was immune to morphine before. I have reddish hair maybe that’s part of it. I’m just really scared. This sucks. I take 20 mg a day of subs right now. Anyone had surgery on subs before?