Do implants look bigger or smaller after they drop?

I am 22, 5 feet, 112 lbs, was a 34A, and got silicone 300cc submuscular transaxillary. I just got my BA done a week ago. They look good so far, but I am concerned they may be too small. My PS measured me and suggested the biggest I go is 300cc because of my small frame. I also tried on some implants under a tight t-shirt in office and the size looked great, but now I'm not sure. Do implants look bigger, smaller, or stay about the same size after they "drop and fluff"?