I noticed facial changes at about 5 or 6 months. I was putting on lipstick one day, and noticed that my lips looked different in the mirror. Something about my eyes changed, too. The changes were subtle, to the point where I can't quite identify what is different. The lips are fuller, but that's all I can pinpoint.
It is not my imagination, because my wife has remarked on the changes too. She was staring at me in the car one day. When I asked what was up, she said, "You look more like Kathy all the time."