Pain in Knee. Again i hitv the ball!

I currently having pain inside my right knee.. an Incident happend almost 9 months ago..During playing football i twisted my knee..at that time I had pain inside the right side of my right knee..after that I took 3 weeks rest by myself.Then I started playing again the pain also coming back...this time its mild one which I can bear...The pain still there which is not effect walking or even playing. 3 weeks before when playing again when I hit the ball with power I heard a sound inside my right knee and I felt pain suddenly.after that I can't even walk properly.At that time I felt pain near the starting of calf muscle.I consulted a ortho specialist Nxt day . He checked me & said that my ligaments are fine . There's nothing wrong with the bones also..He given some tablets for the pain. he also said that there is a chance of swelling inside the knee.I consumed the tablets for 2 weeks..aftr 2 weeks he said I'm okay to play. and the pain is gone. when I started playing again I hitv the ball