After the third run of week 3 I had a slight pain in my knee which has got worse after my first run of week 4. I've seen the exercises for strengthening knees but I've also read that I should rest the knee. Can anyone pass on some advice on how to proceed? I'd hate to have to stop running for a few weeks as the programme is going so well but I'll do what ever is best for the old knee. Many thanks in advance.