While it is true that the nose continues to reduce in size after surgery, this is most often seen in the nasal tip skin. The skin which makes up the nostril (alar lobule) especially in the ethnic nose is often much thicker than the tip skin hence the reduction in the width of nose does not change much after three months. Additional width can be reduced in the future if you have not achieved your desired results. Good luck.
I would say you should continue to wait anywhere from 9-12 months. Even though the reduction and nostril size or the alar base would seem as though the results would come relatively quickly that is not always the case.
Continue to give it time
Chase Lay, MD
double Board certified facial plastic surgeon