I have had ethmoidectomies done. This is when they go into the sinuses and make openings in the bone to help them drain. I didn't have any septal work done. I like my nose. (only thing on my body I do like

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You will probably have some blackening of the eyes if they are doing work on your septum. I have assisted in many of these surgeries. Are you going to sleep? If you have a choice, I would suggest you go ahead and let them put you under. You won't care either way due to the wonderful anesthesia drugs but it will take less time for them if you are asleep. If they keep you "awake", trust me, you won't remember a thing. Maybe a snipet here and there but you won't care at all.
I had a headache the first couple days and then nothing after that. You will probably have some light bloody drainage and they will recommend a gauze pad taped to your nose at first because you might not feel it much. There will probably be some packing in your nostrils that will get removed either just after surgery or in the office. The people I know who have had this done recovered very quickly and felt pretty good afterward. Good luck!