Read This If You Have Knee Pain
While it is not always possible to prevent knee pain, wearing the proper footwear, along with maintaining a healthy weight, building up your leg muscles, and limiting high impact activities can all help to alleviate this problem. Avoiding high-impact exercise such as running, skiing, and playing tennis are essential to the recovery of your knee.
I found a website which has an infograph that shows you pain in the knee and what it means, also health advice on how to try and alleviate it. I bookmarked it because my knees are slowly starting to give out 🙁