Took off fast, and broke down at minute 47, right knee gave a big twinge!! I was running on a flat, the pain is one I am familiar with, it has happened a few times.
My assumption is that the combined hill running - The scheduled 15 hills session, and the 2 long runs I have done that used a route with lots of hills - has caused a bit of damage.
So, I pulled up in the 100 minute run after 47 minutes, and I limped home. Am writing this two days later, and th knee is slowly getting better, it still aches and there is a hint of the pain at times. I have a speed session today so will see how I go with that.