Three factors important to consider when contemplating your return to work are: pain, stamina, and risk of complications. Pain is not bad after most breast augmentations and 3-4 days should work. How much stamina you need for your job is important. Obviously a 10-12 hour shift will require more time off work. The likelihood of physical damage to yourself is another consideration. The problem with nursing positions is that you will very likely to have to do more than what you anticipate. If a fellow worker doesn't show up or is at lunch, and a patient has problems, you could be in a difficult position. I think in your situation, three weeks is a safe answer.