AWESOME!!!! Isn't the first a great feeling and with the health issues even more so. I remember my first century though it took me a bit closer to a year on my Navigator and it was self supported as well. The looks on people's face when you're (in my case 250 lbs) and you tell people that you just finished 100 miles on a comfort bike.
I'm sure now that you've got your first under your wheels, you've been bitten by the bug and you'll want to see how many more you can do. WAY TO GO and I can't wait until I get back to that kind of riding again.