What is hearing a small popping noise in the nose a few hours after having my broken nose straightened in a doctor's office?

Hi and thanks for your question. The sound you're hearing is no doubt related to the unstable nasal bones you have that are clicking in and out of position with minor pressure. If the sound occurs without any pressure or movement it may well be due to some other internal cause which shouldn't impact on the nasal appearance. Either way, your Specialist Plastic Surgeon should be informed ASAP as he/ she may be able to correct things early in the piece. You're in good hands. 

Dear mdmdmdIts unclear if you had a fractured nose and had that reset or a rhinoplasty, butsometimes as the swelling goes up and down in your nose, the air will release from swollen nasal passages and make a sound. your Eustachian tubes may be equalizing as wellits best to discuss with the doctor who straightened your nose. Best Wishes