Knee pain after a fall

Patient: Yesterday I was at a friends house and she has outside stairs and there is a gap between the wall and the stairs its between 3 1/2 – 4 1/2 ft. Well I fell down and hit my knee on the stone ledge and on the ground. I happened at 1:45 am and it is 6:19 pm and it still hurts. My kneecap hurts and when i walk on it it hurts. My father said it is a little swollen and to put ice on it but he wont take me to the docters. What do you believe I did to my knee?

Doctor: According to your description of the pain: during walking, without instability, it may be an uncomplicated trauma of the knee which with relative rest and anti-inflammatory drugs has a good chance to improve in few weeks. But if you have persistent inflammation and pain along with remarkable limitation on flexion and extension associated with instability of the knee other post trauma conditions should be ruled out such as: injuries of ligaments or menisci, if this is the case the strategy would be: evaluation by an orthopedic surgeon and decide about perform some imaging studies to diagnose and decide the best treatment option for you..