It hurts. My calves feel like lead. I discover more bits which wobble that I hadn't noticed previously. All of a sudden there seems to be very little air. And the air that there is feels like travelling through glue. Feeling the need to speed up on sight of another human being...and actually being incapable of doing so. Attempting to convey a 'please don't try and talk to me' smile at said human beings because there is really not enough breath to spare on chat...or smiling come to that. Hills literally get steeper before my very eyes. Ten minutes feel like ten hours. ...