Thanks for the assorted "Get well soon" comments.
I took Saturday and Sunday off running. It was hard to swallow given that I was on track for such a good week, but there wasn't much option. I got onto the Ibuprofen and generally just took it easy.
By yesterday morning it was feeling somewhat improved, but far from 100%. SO I decided to use the ticket to a sports club I have and went for a swim before work. That was fin and I did 2 km in 40 minutes. By theend of the day the back was feeling heaps better and the little hip injury thing had pretty much faded into the background. Great stuff that Ibuprofen.
So I braved a run this morning. I ended up having a reasonably crappy sleep and the back was a little tender when I woke up. This time I decided to a) not force the pace, and b) Just aim for 50 minutes. So in the end it was a very easy 10k in just over 50 minutes at an average heart rate of 126. I felt only mild discomfort and never that I was making things any worse. So if I can continue to nurse it back to health this week while keeping up a few runs like this, I shouldn't go too far backwards.