Awesome! Don't worry, Evan, George will provide Pomfrey with an extra dose of the antidote once it becomes clear why it didn't work. Regardless of whether it becomes public knowledge why he's still a girl, Jamie and Leah will be highly amused with his distress.
On a different note, I was listening to my playlist on shuffle just now, and the moment Katy Perry's I Kissed a Girl came up, my mind instantly went to Jamie and Lucy.