Is it usually the case that patients are charged for revisions?

whether a fee is charged or how much depends on your surgeon and his/her policy - surgeons who own their own surgery centers have more flexibility in this regard

I would definitely follow your Surgeon's advice and wait at least one year before considering a revision; healing for Rhinoplasty takes a full year.  Generally, a revision done by the same Surgeon will be at a reduced rate, depending on the nature of the problem or complaint.  At the same time, a patient is often charged a facility and anesthesia fee for the revision procedure.

I agree with your surgeon that it takes an entire year before all the swelling is resolved and the healing is complete with a rhinoplasty procedure.  It is not uncommon for revision surgery to be performed at a reduced rate or even for free.  Every surgeon is different in this regard.  Sometimes surgeons will operate for free but will pass on the costs of doing the procedure (anesthesia and facility charges) onto their patients. You should have an honest discussion about this with your surgeon to find out what his policy is.  Good luck.