Without further information, it is impossible to answer this question. When was your surgery, what approach was utilized, what extent of surgery did you have, what was your pre-OP appearance of the nostrils, etc.? Only your surgeon has the answers to some of these questions. You should definitely follow-up with your surgeon as the nasal appearance and healing can be influenced even after surgery through compression exercises, steroid injections, taping, etc. However, don't do anything to your nose unless specifically instructed by your surgeon. Nostril asymmetry after surgery can be temporary from asymmetric swelling, or permanent from asymmetric positioning of cartilage grafts or of the nasal tip cartilages. Hope that helps. Best wishes!