Did my first marathon on sunday in Edinburgh. Thouroughly enjoyed myself and muscles aren't too sore after lovely post-race massage BUT my knees and ankles are killing me. What've I done and how do I make it stop? They're sore to touch and when I bend/straighten them. Sitting or standing is fine but movement is agony. Especially going downstairs. How do I make it stop before I'm forced to put in a second bathrrom on the ground floor of my house?