After a surgery most of the patients will have some swelling and scar tissue formation, that usually 3 months later gets soft and then the swelling goes away about 80%, as every patient is different, not all have the same healing process, in your case then the scar tissue it is not that hard and the swelling is minimal. In regard why your skin in the abdomen is still lose, is because everybody needs some extra skin to stretch, so when you bend over, that extra skin shows, specially if your skin on the abdomen has been over stretched from a previous pregnancy. Even skinny patients will have some lose skin, as the pregnancies, aging, loss of weight affects the skin quality. Think that your skin on the abdomen was like an overstretched rubber band, and you cut this rubber band in half, but the remaining half is already overstretched and it will not be as tight as a new rubber band.
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Thank you for the question and photos and your scars are still immature so they are red but otherwise you appear to be healing nicely. If you have concerns though, see your surgeon!