Nelson, I had a bmx and nodes on one side 4 weeks ago and the op was nowhere near as bad as I was expecting.
I wasn't in any real pain afterwards (obviously drugs keeping it at bay!),I did have 3 drains, one for each boob and one for the node wound, they didn't hurt at all, just a bit of a faff when moving about.
They stopped the proper painkillers after the second day and I was just on paracetamol which was fine, I found it was sore rather than painful if you see what I mean. Stopped taking anything by day 4 but because I didn't need it rather than being brave!!
Practical wise, button up pjs are v useful because it is hard to lift your arms up, and cotton if poss cos the hospital was boiling ( I got some cheap ones in Primark) and slip on slippers so you don't have to bend. Normal hospital things such as eye mask and ear plugs are also recommended!
It's odd, it's only 4 weeks ago but seems ages so have probably left loads out, please feel free to ask if you have any queries. CBB wrote a very useful post after her op which was just before mine!