Check ur knee flexon movement if it normal than u r suffering strain so avoid running and other strain full activity do rest heat fermentation pain relief ointment ya physiotherapy treatment both u can If movement is painful so tk MRI to see ligament injury

You may be suffering from osteochondritis dissecans. Better to consult orthopaedic doctor

Coupled with running other fitness activities are important like weight training for your upper and lower limb! Also proper warms and cool downs are very important! If you r doing everything correctly then you need to get your knees checked for proper diagnosis.

Hello! Advices to reduce your knee pain 1. Reduce your body weight if you are overweight.as it causes load on the knees as you run. Opt for other exercises to reduce body weight. 2.if you weight normal to your age then- do compulsory warm up before running or jogging. This will make your knees ready. 3.do strenghtening exercises for the quadriceps, hamstrings and calf. 4.do cool down and stretching exercises to bring knees back to normal state. 5.apply ice pack wrapped in a towel after your activity around the knee for 10 min. Consult a Physio for strengthening your knee