When you've got experience, it pays.
My beautiful dappled gray welsh mountain pony, Bubbles, (he's not really mine), has been abused terribly. He is afraid of everything under the sun, poor baby!
Well, I've fallen off him twice because he spooked and had just caught sight, out of the corner of his eye, a whip being put back into it's holder, and did a HUGE sidestep and a start, and I nearly fell.
But having six years' experience in riding, I kept my heels down, sat deep, and squeezed my legs around his middle. I circled him again and patted him and he calmed down. I didn't fall. I didn't lose my head and I comforted him, then proceeded to have a good lesson.