Right knee/hip joint pain

Hi!

For about a year my right knee has made a gliding/catching feeling on the outside with each step. It comes and goes but has not pain or swelling associated. In the last few months the outside of my right knee and my right hip joint have been hurting - still no swelling. Usually happens with running but also if I have been sitting too long. Pain doesn’t subside quickly with stretching. Would love any suggestions on what this could be and how to rehab it!

Thanks!!