After a breast augmentation and/or breast augmentation with breast lift, especially in the sub muscular position, the fluid (whether saline or silicone) is usually pushed to the top of the implant, therefore giving a greater fullness on top rather than the bottom. This increased fullness on top is a temporary malpositioning of the fluid within the implant itself from muscle and skin pressure upward.As the skin and muscle stretch out, there is a process facilitated by gravity known as "drop and fluff". I believe this process is not one of implants moving down but fluid in the implants migrating downward with gravity and often with the help of an ace wrap or bando over the upper quadrant of the implant.As for squareness at the bottom of the implant, one often sees this early after a standard breast lift before the implant has moved down in the middle of the breast lift, giving a more rounded bottom. However, I have never personally seen a square looking breast after just a regular breast augmentation, and therefore I find myself unable to answer that portion of your question.At this point, I recommend you pose this question to your personal plastic surgeon who I am sure can explain your early post surgical breast appearance.