I can relate to times like that. I'm up now...and I don't really have a reason. It seems like there is always so much to do and definitely think about. My son was sick at one point over the holiday. Our whole family had a virus and it was the pitts. Hang in there! ((HUGS))
The only thing that ever helps when I can't turn off my brain (and that happens to me ALL the time) is if I sit down and write a list. First list is of everything I need to do...second list is everything I am worried about, stressed about. Somehow writing it down helps my brain to stop going over it again and again...kind of like the worries are in safe storage :)
I remember when my little one was sick before he could speak...it is so hard and scary because they can't tell you what they need or how bad they feel. I used to get so anxious until the fever would break and he was resting comfortably...so sorry! My thoughts are with you. Feel better soon...both of you!