Outstanding first effort, Kevin! Having the guidance of a master didn't hurt either. It took me dozens of tries before I produced something half that nice.
You probably found out that the actual turning on the lathe is relatively easy and straight forward. Mechanical stuff. It's the shaping on the disc and finish sanding that takes the skill developed over time (and lots of ground up fingers!). Concentration and focus is key, as the disc can be unforgiving at times. You can take wood off, but you can't put it back on. One big slip and it's scrap.
Again, great work! Enjoy!
CACooper