My bum is still flat after my Lipo 360 BBL (fat transfer) it's been 4 days! Is that expected?

Without viewing before and after photos or knowing how much fat was injected, it is difficult to provide specific reasons for your results.  Recovery from lipo 360 and BBL is patient dependent. Much of this depends upon the amount of liposuction performed and the amount of fat transferred. I have observed that between 4 and 6 weeks the buttocks tend to stabilize in volume.  Follow your PS's post operative guidelines.  Usually by 3 months, the swelling is minimal and totally resolved by 6 months.   Recommend you wait until six months to evaluate final results before making any decision to consider a revision.
Kenneth Hughes, MD, ABPS Board Certified Plastic Surgeon
Los Angeles, CA

Dear Fierce1627,
I understand your concern. However, without a proper assessment, it would be difficult to determine what is wrong. It is best that you visit your plastic surgeon for further assessment or ask for a second opinion. Only after a thorough examination, you can get proper recommendations and advice.
Daniel Barrett, MDCertified, American Board of Plastic SurgeryMember, American Society of Plastic SurgeryMember, American Society of Aesthetic Plastic Surgery

Hi and
welcome to our forum!
Congratulations
on your recent procedure...The procedure of BBL is an
"insult" to the soft tissues, resulting in swelling which will
initially totally obscure the operative result. How much fat was grafted to each buttock? The
purpose of a compression garment is to prevent bleeding and to control
swelling. We usually recommend its use for the first 4-6 weeks after the
procedure. 60-80%
of the swelling should subside within the first 6 weeks, with the remainder
slowly subsiding over 6-12 months. We recommend total avoidance of pressure to the buttocks for 3 weeks. 
It is far, far too early to assess the operative result. Swelling must subside and your overlying skin and soft tissues must remodel to accept the new volume. 
Continue
followup care with your plastic surgeon.Best wishes...

That is not normal. Do you know what technique the doctor used? There should be a huge difference before and after. If you are a good candidate for a Brazilian Butt Lift (BBL), the optimal outcomes are achieved with: 1) use of VASER liposuction to harvest the fat, 2) a closed looped system such as Puregraft to process the fat, and 3) strategic micro-packet transplant technique. These three processes have demonstrated over 95% fat graft take. This means that your results will be stable as long as you maintain your weight. As an official VASER trainer, I am routinely referred unhappy BBL patients. One of the most common reasons for disgruntled BBL patients is that patients are not able to accurately communicate their desired buttocks goals to their surgeons.  A buttocks assessment tool can be an invaluable tool to communicate to your surgeon the exact buttocks size and shape you are desiring. A Skype or FaceTime consultation with a BBL specialist can help you get an accurate recommendation and pricing.
Respectfully,
Arian Mowlavi MD,FACS
Realself 100 Hall of Fame Inductee