What could be the cause of a nose tip changing shape with an unexplained lump and is rhinoplasty the only solution? (Photos)

Over the course of a couple of months my nose appears to have changed shape. Previously it was smooth and now I have what feels like a small pea sized lump slightly off centre on the tip. A dermatologist told me it was just my nose changing with age. Is it possible for the tip of the nose to change "so quickly" and what could be behind it? I thought it was a cyst or papsule at first until I saw him. I have included a photo of how it was 6 months ago and then one from this week.