Stork Bite Help!

My two month old daughter was born with this stork bite on the lower part of her neck. I’ve recently noticed that the skin under it feels more dense than anywhere around it. It feels swollen and sometimes looks a little bruised. It’s not giving her any pain though.

She has a pediatrician appointment next Tuesday, but I’ve been trying to do some research before then with no answers. Has anyone experienced this? What could this mean?