Emma opened her mouth a time or two, closing it and opening it again as if to try and find an answer that wasn't insane before she remembered that this whole thing was to do with her magic and learning more, and maybe it'd help if Gretel saw that Emma could do what she said she would
"Well, I'm practising, my aim is a little off," because she didn't actually want any of this junk, "but I'm getting there." She might, eventually, need to concede to taking a quick look in the hospital, bluffing her way in and back out, just to get a general feel for the place before trying seriously to get the insulin medicine.
"But as you can see, everything comes through entirely intact, so..." it was progress, and better than just toast.