Bruised Muscles, Bones, Pain. How To Deal With It?

I fell on a wobbly bench and hit my left kidney area on the side of the upright bench a few days ago. It seemed bruise and the pain was manageable even thi morning. I can walk with not a great deal of pain, but laughing, sneezing , or tryi g to sit up caused a great deal of pain. There is no blood in my urine. I have drank gallons of water over the last few days. Was fine, but today I carried some items up and down stairs seemingly straining the already bruised muscles or bones there. Now it is difficult to move around to sit up. Once I am up on my feet , the pain is minimal and I can walk, but moving my torso, breathing deeply, laughing, clothing, and worse, sneezing cause a great deal of pain.