Knee pain and swollen ankles. what could be causing this?

Get them evaluated: This is impossible to answer without an exam. Are the ankles painful or is it just fluid retention? I would start with your own doctor if you have one.

Many causes: If multiple joints are hurting and swelling without an injury, i recommend an evaluation by your primary care provider. An orthopedist and/or rheumatologist may also be recommended for a thorough evaluation of possible arthritides.