Long story short: 1. As soon as I sat down they told me my written portion was a "strong pass" -- woot! 2. The session was planned for two hours; I was done in 30 minutes -- woot woot!
Apparently it was all in my head. But seriously, last night I finally worked up the courage to look at what I wrote. It was shockingly coherent and not at all reflective of the chaotic turmoil I experienced while writing it.