Hi, thank you for your question. It is not unusual to feel tired three weeks after surgery. After receiving general anesthesia (I'm assuming this was your anesthetic since the case lasted four hours), many patients feel tired and sluggish for about a month. You may have days or periods when you feel normal and with the regular level of energy, to be followed by periods of fatigue. I advise my patients that this effect will wear off, and that it's best to listen to your body; if you feel like taking a nap (and you're not at work), do it. Younger patients bounce back faster, but those of us age 40+ need a bit more time to recover. If your fatigue does not resolve in the next week, please let your surgeon know.Best wishes,Dr. Naidu