ME - temperatures are frightening things for little ones aren't they (even when they are bigger lo's). I'll bet it did set some alarm bells ringing with you.
My DS is sleeping in til 11 since getting out of hospital (there's an evil part of me likes this virus) and having anything up to 5 hour afternoon naps. Seems like it is the bodies way of shaking this virus, and your DS is doing a good job!
Would seriously recommend Nurofen syrup if you haven't used it already - it was the only thing that touched my sons temp, and worked within half an hour.
Look out for a viral rash. I took DS to doctors yesterday, as though he had had a pinprick type rash throughout, it developed into big purply blotchy spots yesterday. This rang some bells with me, as you can imagine. They were just part of the virus though, and have gone today.
I hope your DS is feeling a whole lot better soon! As Wabbit said, go with your instincts. (I didn't have to think - I had no idea, but the doctors think my son had either had a febrile fit and I had found him afterwards, or he was about to go into one and I found him before).