Fever update

It was a rough night. Kate was up every three hours. The first time she was wide awake for about an hour. The rest of them were very short. A bit of nursing and back to sleep. I checked her temperature in the middle of the night and it was still reading 102, although she felt a lot hotter than that to me. This morning it's down to 100, and she seems totally fine. How come she's not exhausted after being up so much, but I am?