Yeah it's hard keeping up the motivation as you get older. More things to detract you. When you're younger you don't know any better, if you're good or bad. You just are engrossed in the art. I'm envious of the people that can maintain.
I did this when I was working in video games so I think I spent 2 nights pounding it out (about 8 hours total). I am slow... I still remember scanning it and email it out at like 3 in the morning from work.