I fell down some stairs and behind my right knee and on the right side it hurts. I do have some brusing on the calf. But behind and the side it feels stressed and hurts. Can I use a knee brace and IB to help with the pain or could it be worse. I know nothing broken I can walk.

You really can't know whether you broke anything until you have an X-ray. Why not make a doctor's appointment for an exam and possible treatment?

You can also educate yourself, a good idea no matter what. Google "knee injuries" for starters. If you fell so that your leg twisted as you fell on your knee or the side of it, a common condition might be ACL, a damage to a ligament. Of course use a knee brace and ibuprofin and Tylenol (I take both). Keep flexing gently throughout the day, and try not to sit in one spot without moving it every few minutes. Take warm baths or showers. Keep it WARM and MOVING but only gently.

I once feel down some steps and had a huge swollen ankle with a huge bruise - but it was the tiny pain on the front of my knee that lasted for years. It was synovial fluid leaking out of the sac on the knee.

There are several ways to damage a knee.