Hello dear user! I have gone through your query and understood your concerns! Thank you for sharing them on healthcaremagic. Its understandable that traumas especially in articulations lead to edemas and difficulties in moving them. Knee articulation holds almost all the weight of the body and is responsible for the stability during walking. The pain and swelling is due to inflammation of the articulation, as a response of the organism to the hit. It may be associated with liquid collection in the articular cavity which can make the walking even harder. I would recommend you to keep cold compresses on the knee and take antiinflammatory drugs for the inflammation and the pain. Ibuprofen, diclofenac are the most used drugs in this case. Vitamin C, is also used in knee injuries to help it recover quickly. Bending articulation would help to reduce edema. If your symptoms persists for too long or get worse please go to your healthcare center and see an orthopedician because you may need a MRI to evaluate your bone, cartilages and ligaments structures. Take care and all the best for you! Please kindly rate this answer as helpful. Best regards! DR ERIOL.