What Causes Joint Pain In The Knee After An Injury?

Hi Sir I am Joydeep. day before tomorrow i had a injuries in my left knee join. i am immediately go to Kolkata Medical College. After Done x-ray Doctor check up me and nothing to worry. there are no any fracture or others. but when i walked sometime join dissemblance and i fall down . i feel no pain in my knee join but when i walk some feel bit of pain. My question is my ACL Injured?