What Could This Hard Bump On The Tip Of My Nose Be?

In the last 6 months, a hard, protruding bump has formed on my nose tip . An ENT examined it and said the tissue had shifted because of a septoplasty from 5+ years ago. However, he did not actually touch it, and I am somewhat skeptical of this diagnosis because the bump is nearly as hard as bone, and the tissue in that area did not used to be hard at all . Furthermore, other than the bump itself, the rest of my nose is exactly the same as it was before. What else could this bump be? Thank you!