There is a rounded ridge where my gums meet my new dental crown, is this normal?

Without seeing you in person, or seeing a very accurate close up photo, I could not give you an opinion at to whether or not that is normal.  However, your periodontist, who IS a gum specialist, and has personally seen and examined your gums and bone, is the best one able to give an opinion.  My advice...listen to your periodontist and don't worry.

As your
periodontist has checked it and if you have no pain or irritation then you have nothing to worry about. A periodontist specializes in gums and is the best person to
assess gums.  So as you have assurance from a
gum specialist, I would not be too concerned.