Try moving as hard as you can
From Create Your Own Story
As you struggle to move, nothing happens. Suddenly, you hear a loud bang and see a flash of light. A small wizard with a wispy beard falls to the ground, stunned by Snape.
"STUPEFY!" A flash of red light. It ricochettes off of the wall and hits a witch squarely in the chest. Snape begins to jump over chairs, and he is shooting spells at the rest of the witches and wizards. "PROTEGO!" Another bang. You realize that all of the wizards in the room have suddenly begun to shoot spells at one another. During the chaos, the Body-Bind curse put on you wears off.