2 weeks post op- will Sientra (385cc) textured round implants drop or get any smaller? Will they come in a bit more? (photo)

At two weeks you still have a lot of swelling. At 3 months you will have an idea about your final size.

I think your implants look nice at this early post op stage. They will not move in position much, and certainly won't migrate toward the midline. Your breasts are spaced relatively widely, and this anatomic fact determines implant position in your case.