Hi, I Fell Off A Ladder Today. I Somewhat Jammed

Hi, I fell off a ladder today. I somewhat jammed my left leg back on the ladder, then fell sideways to the ground. My back calf muscle, back of the knee is painful, hurts to walk, and I have swelling and pain above my knee cap. I am wondering if I just hyper-extended it... I feel I would be in a lot more pain if anything else... I was walking quite a bit, bending, right away for a few hours, and then it really tightened up, swelled, and hurts more to put weight on it.