I've been training for the Nottingham Half Marathon for six months and now, and with a week to go I've got a gammy knee. It first started hurting last week after an 11 mile run. Three or four hours after the run, the outside of my left knee start to get tight. It also started to click when I walked.
It's now fine when I'm walking but as soon as I start running it gets tight again and feels kind of twisted but as soon as I stop running it's fine with the occasional twinge.

It clicks sometimes when I walk.
Any advice please. My half marathon's on Sunday and I need to run it cos I've raised lots for charity.
Thanks,
Tommy