525cc, look small. Will they get bigger? 4 weeks post op

Yes, you are early and the tissues are compressing the implant and making it look smaller. Over the next two months they will look more natural and fuller. The 525cc are not small-they are large.

Dear michellem6,Dropping of implants is part of the healing process and this
occurs after the tissues surrounding the implants slowly relax, allowing the
implants to settle into their final position. It can take about four to six
months for the implant to drop down to their final position. You are still in the early phase of the recovery
period. Please do allow some time for the healing process to occur. If after
six months, you are not satisfied with the appearance of your breast, you can
visit your plastic surgeon and discuss your concerns.Daniel Barrett, MD, MHA, MS 
Certified, American Board of Plastic Surgery 
Member, Am. Society of Plastic Surgery

but the distribution of volume will change and may give the look of being fuller.  If you desire just small amounts more, you can always consider fat grafting down the road and that can be done in the office.