Me too! Except with Pathfinder, though. I tried working up to running a campaign a few years back, but I failed back then. The closer I got to actually delivering, the worse I felt about it. This time around, something had changed, and I was able to carry out the inception of not just one, but two campaigns (two different gaming groups). Pretty chuffed about. It was a part of the hobby that I had to try, since I was pretty sure I'd be able to bring something to the table in that regard (and enable the other GMs to try being players again). I still stutter during, but most of the time it doesn't matter. And most of the NPCs are "foreign" to me (some are improvised or not frequent occurrences), which can help in maintaining fluency.