Writing jitters

I emailed someone feedback for their fic about a week and a half ago saying "great fic etc, and there was this one line that hurled this plot bunny at me..." and she replied saying "please, please write this." So I kinda have, wrote it over about a week, with uni assignments languishing terribly by the wayside. I've just sent it to her, going "um, interested in reading?" and my palms are literally sweaty.

I had planned to start that essay that's due on Friday, but writing all day has left me mentally dazed and, god, the nerves!