In an amphirhinal report for Vox, video producers Christophe Haubursin and Julia Belluz explain why one’s nose looks so much bigger in selfies than it does in photos taken by others. This is due to visual distortion due to the distance between camera and face. Longer distances will appear to flatten features, while shorter distances cause the most prominent features to be bigger than they actually are.
A team of researchers found that taking a photo from one foot away, makes the base of the nose look about 30% larger and the tip look 7% larger, than they would from a further distance. From five feet away, your features are flattened. From a foot, your nose is exaggerated.