DD has not slept properly for 2 nights. Both nights she went to bed at the normal time, and woke up a couple of hours later, crying, with a temperature. She is absolutely full of cold - a really bad one. Last night I couldn't get her back to sleep til after midnight, and even that was fitful. I've been up about 20 minutes and she is still asleep. Do I let her sleep longer? I can't even keep my eyes open