I fell on my knee yesterday and now i can't bend it or put weight on it it's also very swollen and red and bruised, do you think it's fractured?

Very Possible: If you have pain with weight bearing or are unable to weight bear you need to be evaluated by a physician and an xray to evaluate for a fracture.

Possibly: You should ice and elevate your knee. You should be seen by an orthopaedic surgeon who can examine the knee, take a good history and decide whether xrays are needed to look for a fracture. He/she can also help with bracing, medication, physical therapy, and any other treatments that will speed your recovery.