First time running after a week layoff, my knee issue turns out to be an iliotibial band problem, so spent the week resting with regular small bouts of stretching and strengthening exercises.
I decided to run rather than rest longer as had had no pain for last 3 days, took it easier to try and make sure I didn't stress it - In the end my pace was only marginally slower even though I thought I was going much slower, and still did 5k in 28m 10s... Knee was fine until the end where it started to ache, but not the full on pain from the last run. Finishing there and walking home for 5k was no problem, some small twinges and some ice when I got home and seems fine right now. Will wait till Friday for next run though.
Glad it wasn't too bad in the end, the day after my run when I realised I might have to have along lay off was quite disheartening, it's funny how quickly it became the norm to run...