there is nothing wrong with your model, the vertice difference is purely a custom choice in the preferences, Kurt made the tutorial a long time ago when sub d vertices used to display the sub d density level hence why there are zeros, if he refined the mesh by selecting it and hitting finer the zeros or circles would change to the number 1, it is simply a method to show the current sub d level you are on and wont hinder your model in anyway.

If you want it to look like in the video simply go to Windows -> Setting/Preferences -> Preferences -> Subdivs -> Numbers