I haven't had LD flap, but have been through 15 surgeries for breast and endometrial cancer including double mastectomy and DIEP surgery. It can take a year, sometimes more, until your body fully recovers from any kind of surgery. Even though your skin is healed on the surface after 3-8 weeks, there's still a lot of internal healing that goes on inside your body. It's possible you are still experiencing swelling from the surgery, but you could also have a seroma or lymphadema. If you haven't talked to your doctors about the swelling and had them examine it you should do so sometime soon. Good luck ❤️