L is sick with croup and it's our first time dealing with this. Any advice for this worried and exhausted mama?

We got her checked out by the doctor today and it seems to be a mild case (no steroids prescribed). However, this cough is so awful and she is having fits that are waking her up. She's thrown up once from coughing so I feel like I need to keep a close eye on her.

She's currently sleeping in her crib and I'm camped out on the rocking chair because I feel like I need to be close by in case she can't breathe.

Help convince me it's ok to go to sleep!!