It's my left knee that is swollen i'm not sure if it's from a twist but certainly not of fall i don't know what to do the pain is here thanks?

Need exam: Swelling means inflammation. You can have a meniscal tear, ligament issues, arthritic changes within the knee. If the swelling doesn't go away with some short rest, ice, anti-inflammatory meds like ibuprofen, then see your doc or orthopedic specialist. It might be time for an mri. X-rays only show boney problems, and most knee issues are soft-tissue related.

Go to theer for eval: Atraumayiv joint effusion need fluid analysis to arrive at DX and the er can help with pain.