What did I do to my knee?

Last Sunday, June 5th, I was playing soccer and collided with one of my friends. His knee banged just above my knee, and it hurt pretty bad. He was fine, but I had to stop playing. I sat out for about an hour and iced my knee on an off. After this I was fooling around after and got tripped and as I fell, I hyper-extended my knee, and that hurt pretty bad. After that I stopped playing for good. I know I was very stupid for doing this. I got x-rays and they said I had a really bad muscle contusion. Later, on June 11, I went to the ER, and they took x-rays and saw nothing wrong. They also drained the fluid from my knee which hurt pretty badly lol. Now I'm on crutches, and my knee has been swollen since the accident. The orthopedic at the ER said to see my orthopedic and I scheduled an appointment for tomorrow. He said he thinks I may have torn something but he isn't positive. I'm guessing I'm going to get an MRI tomorrow.. but does anyone know what the worst/best case scenario is for me?? Thanks!! :)