It is not uncommon to not have a perfect result immediately. There likely is swelling that is causing the problem. If fat was removed this may be adding to the change of the lower lids. See your surgeon often to get reassurance but don't look for further action for months.
Wait till swelling is gone
Please wait till swelling is gone. Discuss your concerns with your doctor and if you have lost your confidence get a second consultation from a board certified plastic surgeon.
It will probably improve as you heal further
It is difficult to say without seeing you in person. Sometimes, swelling takes a little longer to resolve and hopefully it will improve for you shortly. Discuss this with your doctor again. You might benefit from a lyphatic massage by a specially trained aesthetician. You might need a filler injection in the future as well, but I would wait till the swelling is gone.
While there are many horror stories of excessive removal of tissues from the lower eyelids, the majority of patients who have your complaints are the result of swelling to the lower lids. It will take up to 6 months for the swelling to resolve. So, relax and follow the advice of your doctor.
It is probably the swelling
Desperate, Without seeing a picture or examining you, it is hard to tell for sure. However, just three weeks after surgery there is still a considerable about of swelling, so you should not get too discouraged. Hang in there.
It is a little difficult to answer your questions without a photograph but there are several generalizations that can be made at this point:
1. You are still very early in the post operative period and swelling is a likely possibility.
2. You mention some drooping of the lower eyelid, this could be a condition known as an ectropion. There are several causes for an ectropion including early swelling.
3. You mention some hollowness of the lower eyelid area but you did not mention whether or not you had any bulging fat of the lower eyelids prior to surgery. I am assuming you did not and that you were using soft tissue fillers to add volume over the contour depressions known as a tear trough and naso-jugal creases.
You simply need more time at this point to evaluate your result. Have a conversation with your surgeon and express your concerns. He or she is in the best situation to know exactly what your anatomy was like and what was done to rejuvenate your eye area. Ask your surgeon if gently massage of the lower eyelids would be any help.
Three weeks is too early to tell final Blepharoplasty results
3 weeks is too soon after surgery to know what the final result will be. It is tough to look in the mirror and not be happy, but this is the time that you need to honker down and be patient. It will take months before you see the final result.
If your lower lids are drooping, ask the doctor if supporting them with steri-strips will help.
Even if you are not happy with the result, something can usually be done to "touch up" and get you happy. Don't get discouraged yet.
It can take 6 to 12 weeks to see final blepharoplasty results
Please relax and don't be so worried. You are only 3 weeks out from your blepharoplasty and the swelling is surely pulling the lids down. You will definitely improve over the next 4-5 weeks. This is a passing phase.
If after your recovery you still see the hollowness beneath the lower eyelid and cheek area there are other things you can do.
I do not use fillers on the eyelid. The eyelid skin is so thin that discoloration and lumps are common. Open fat grafting can improve the hollow upper cheek and lower eyelid area.
For now, be patient, you should be much happier in a few weeks.
Post-Operative Blepharoplasty Concerns
This is a very real possibility, so I always advise patients to give things a full 8 weeks before starting to make assessments as to its success. The other possibility is that you had an underlying preexisting lid ptosis or droop that was not adequately identified pre-operatively, and now you are seeing it very clearly due to the removal of what was overlying excess skin.
Likely what you have also described is filler such as Perlane to the tear troughs, which can really create a nice cosmetic improvement. Unfortunately there is no permanent cure to this aesthetic challenge.
Three weeks after surgery is a short time
This is a very short time after eyelid surgery as far as your body is concerned. I would give it a full 3-6 months before any judegements can be made. The healing process can take up to one year and to be honest as far as your body is concerned three weeks is a very very short time after surgery. You need to give it some time.