I see you posted roll. Don't worry about screwing it up. The only way to screw up roll is by not being on roll.
You are right, coupling the physical fog of withdrawal with the physical pain of your surgery/hospital stay will and has done a lot to mask withdrawal symptoms. Keep in mind that at some point you will be completely recovered from your surgery, and it will be back to life as normal. You'll fall back into your old habits, and nicotine will be right there waiting for you.
You see, you, like me, are addicted to nicotine. And, the mental part of addiction is stronger than the physical part. If you let your guard down, and give nicotine a crease to enter back into your life, you'll be a slave again in no time.
My point - don't underestimate how badly you'll want a dip three months, or a year from now. Those cravings that come out of nowhere, and smack you square between the eyes are very real, and very potent.
Make your promise. Keep your promise. Repeat daily.