Hi Michelle
I've had that happen with both of my children aswell. It's great advice Jenni has given regarding mentioning it at your next Endocrinologist appointment.
In both cases the kids didn't wake up as usual so I went in concerned and they could barely wake up. In one episode my daughter when she was around 10 months old managed to make a peep but by the time I took her to the loungeroom she was completely unconscious. That ended up being the first time I used my hydrocortisone injection equipment. It was a much more secure feeling driving her into hospital knowing she was covered with enough cortisone. I think sometimes they have been unwell the day before or while they have been sleeping but there haven't been any symptoms and it's pushed their limits through the night. Babies and young kids can get very sick quickly and can also recover very quickly.
That being said I've had times when we have given them fluids and tripled their dose and they haved bounced back within the hour. Obviously what ever you did worked because she came around fairly quickly.