Why are my nostrils different sizes? (Photo)

Hello,A deviated septum means that the wall in the middle of your nose is tilted. This can cause uneven nostrils and breathing difficulties. I do not believe that you caused this. To fix a deviated septum tiny incisions inside the nose (no external cuts or scars) to access the deviated portions of septal cartilage and bone. We then removes or straightens these deviated portions in order to rebuild a completely straight septum for 100% patient nasal cavities for enhanced breathing for life.All the best, Deepak Dugar, MDScarless Rhinoplasty ExpertBeverly Hills, CA 90210

Difference in size is not huge. Symmetry is very rare in human noses if you. If you're bored by this could definitely be corrected surgically but I will not recommended at this point

Some patients develop a deviated septum from severe trauma to the nose, such as with nasal fractures. Most of the people that have deviated septums simply have it and did not have any trauma. The septum just was deviated at birth or became deviated with growth. Deviated septums are very common and if they cause breathing difficulty you can usually get insurance to cover a septoplasty to improve your breathing.

Asymmetric nostrils are completely normal. No human beings has perfectly symmetric nostrils, arms, legs, etc. on both sides. Some asymmetry is always normal if you look closely enough. Your small differences are easily within the range of normal and nothing to be embarrassed about!
-Dr. David Mattos, New York Plastic Surgical Group

this is very common and U did not cause a yourself.  There are changes to the skin as far as thickness is concerned and rigidity of the nose overall as you age.  This is particularly true as you go through puberty.  You did nothing to cause this but you may have breathing issues related to the deviated septum and nostril asymmetry.

HiVery few noses are perfectly symmetric.  In fact 85% of people have significant facial asymmetry.  Most of us have different eyes and cheeks and ears and jaw lines and even hands and feet from left to the right side.  Perfect symmetry is rare.What you are seeing could be a combination of the caudal septum (google it) pushing to the right side &/or your right lower lateral cartilage (google it) being a different shape than the left side.  Also, your nose at 6, 16 and 60 is not going to be the same.  The entire face and body go through changes and these changes could have been unrelated to you "pushing" on your bridge.  But stop pushing on your bridge please.  You could have caused your septum to buckle if you were pushing on the lower end of the bridge.  

A nasal septal deformity or a curve in the nasal septum can often cause nostril asymmetry.  It sounds as though you have had an intranasal examination and my presumption is that the doctor who performed this  is correct and that you have a nasal septal deviation.Often a septoplasty can correct this problem.