I've had two - one emergency and one planned.
With the second, I was not given any codeine or iron tablets, just paracetamol and ibuprofen - not even any stronger than you get in the shops! Told it was NHS cost cutting. I was really scared they wouldn't be enough, but it was actually fine - I kept taking them religiously at the recommended times, and the benefits of no constipation and feeling much less 'drugged up' were good.
BIG recommendation if you get trapped wind - I had it terribly, it was the worst thing about my second c section and peppermint did absolutely nothing - try Rennie Deflatine. Took me from agony to painfree very quickly (via millions of farts!!!)
ALSO do read the leaflets they give you about post c-section exercise and actually do them (when you're ready). I had diastasis recti (split abdominal muscles) whilst pregnant with my second, and didn't realise that c sections really make this worse, as they cut straight through all your core muscles. So I have now been in physio trying to fix it, 9 months after the cs. Would have been much better if I'd done the exercises post c section in the first place.
Take LOADS of magazines into hospital - I was due to go to theatre at 8am but they had lots of emergencies so didn't go in until 4pm. Got VERY bored (and hungry!)
Good luck! It really is a very civilised way to give birth!