..and what should I do about my knee pain?
Firstly to clarify you do not need to be a runner to have Runners Knee. You might be skiing, gardening, playing tennis or just dealing with day to day activities.
Secondly Runners Knee is a non medical term and can be a couple of different clinical issues, primarily related to the kneecap or the lateral part of the knee where the ITB can rub on the lateral condyle of the knee due to changes in the forces going through it from the muscles and movement above.
Find out if this might be your issue and what you should do to get on the right track again.