Regretting sliding genioplasty. Bottom lip is thinner and chin is longer than before, can this be reversed asap? (photo)

The first thing to realize is that what you are seeing at just two weeks after surgery is not necessarily the final result. Because of swelling the shape of the chin may eventually be different than what you are seeing now. You may think what you are seeing is the final result but that does not necessarily make it so. It takes a full 6 to 12 weeks to see the true final result from any facial bone surgery. Your chin may or may not be actually longer with a sliding genioplasty based on the angle of the bone cut and how it was secured. Temporary changes in the smile and lip movement are very common after this procedure and those will be a self-solving issue with more healing time. Your genioplasty can always be reversed or adjusted, even after it is healed, it is just easier to do that in the first six weeks after the initial surgery.

It will take several months for all of the swelling to go down.  The firmness you feel will likely also soften with time as the bone will remodel a bit.  Try to be patient with the healing process.

Best advice is to go and talk with your surgeon.  The surgeon that did the surgery may well be willing to reverse it with minimal cost to you (you will likely be asked to pay for OR and anesthesia).   Or your surgeon may suggest you wait for 6 to 36 weeks and you may grow to like the result.  Or assess week by week.  Often it takes time to appreciate the positive of plastic surgery.  Being patient may well be the best advice.  Go talk to your original surgeon.  My Best,  Dr C