With FMLA you have a total of 480 within a rolling year, which means everyday you can get another day back if you took time off at the same time last year. So go back and calculate how many hours you have missed, so that you know exactly how much time you have actually used. When I had my surgery I was back at work the following week but I have a desk job, so it might be different for you. Also, after my surgery I did not experience any pain so working was not an issue.