Deviation and uneven nostrils after revision rhinoplasty. Bad rhinoplasty or uneven swelling? (photos)

I appreciate the photos that you have sent regarding your revision rhinoplasty and nostril asymmetry.  It appears that you have fairly thick nasal skin and therefore it will take longer for the tip edema to resolve.  What I can see at this time however, is that you have an issue with the lower lateral cartilage on the right.  It appears to be buckling and may be weakened from your two surgical procedures.  The buckling of the lateral crura of the lower lateral cartilage has led to nostril asymmetry, slight notching and some external nasal valve collapse and tip deviation to the right, the side of the weakened cartilage.  It is too early to worry but certainly not too early to keep an eye on this issue.

20 days is still very soon after surgery, and swelling will influence the appearance of your result. In general, swelling can give the appearance of:1) Asymmetry 2) IrregularitiesI would recommend giving it some time and see how you continue to heal, as the nose changes over time. Your surgeon should be able to answer any questions regarding healing, as he/she knows the details of your procedure. I hope this helps, and I wish you the best of luck. 

Swelling after rhinoplasty is expected.  More swelling with revision surgery can also occur,expecially if grafting was required. Unfortunately, both sides of the nose do not always swell the same and can heal at different rates.  Uneven swelling and nostril asymmetry can also be related to the types of grafts that were placed in your nose, if you had any grafting.  3 weeks is way to early to make any estimation.