Long distance running

I have been running for just over a year now and as of this week have started to really train for long distances. Where I've ran anything over 10 miles previously, I have found that my knees become really sore for around 48 hours afterwards, and I walk a bit like a cowboy. I always run outside, usually on concrete.

I am considering using knee straps/supports specifically for running to try to combat this problem - does anyone have any experience of this?