Knee pain? Advice?

A while ago i went riding with my sister on her skateboard. When we suddenly started to try out a crazy idea of ours. We decided to sit on the skateboard. Anyways we continued taking turns sitting on the board being pushed by each other. When it was my turn to sit on the board again. But instead of my sister giving me one big push like we were doing she kept pushing me and i felt unbalanced on the board so i tried to stop it. Which was not a great idea cause she was still pushing and she landed on top of me. The board was between my legs she was on top of me her hands were under the board it was a tangled mess that i couldn't figure out. That and i was so focused on a knee pain. I thought i broke a bone but i wouldnt know how that feels since i never experienced it. My knee was pushed sideways (to the left) it felt horrible. I couldnt stand, i sat there for a while eventually the pain went away. Ever since then my knee kinda bothers me sometimes i feel a little pain when i stand. But last Night i kept bending my knee over and over hoping it might help. Later on that day the pain got worse. when í tried to stand up, walk or stay standing. Even now as i lay down writing this it kinda bugs me. Not to much but a bit. Any idea what i tore? Or what you might think happened with my knee? Any suggestions on healing? Its not swelling or anything my knee looks fine. Its just something with the inside of my knee that gives me pains occasionally