10 Best Physiotherapists in Pb.Urban Development Authority, Ph-8

Even without swelling, pain can happen due to injury or overuse. Rest your knee, ice it, and elevate it. If the pain doesn't improve in two days, seeing a doctor is wise. Many potential causes exist for knee pain without swelling. Resting, icing, and elevating are good first steps. If the pain persists, seek medical attention.

You may be having a health problem called arthritis in your leg. Arthritis attacks the joints and causes pain, swelling, and stiffness. It is when the cartilage, which protects the ends of your bones, wears out over time. To relieve the pain, you can learn some gentle movements, use hot and cold therapy, and take over-the-counter painkillers. 

I think you got a scratch on your knee when you fell. It's okay to have pain, redness, and swelling around your wound. This is because the fall has injured your skin. The solution is to gently clean the wound using soap and water, apply an antibiotic ointment, and cover it with an adhesive bandage. Always change the dressing daily until it heals. Opening up is necessary if the pain worsens or you notice any infections with symptoms like pus, light redness, or warmth.