I had the exact same thing happen a while back. My mare jumped a creek and when she did it all I saw was her feet and belly coming at me and I thought I would be landed on, but I wasn't thank goodness! She is a good mare, lol!
But it was my fault, I have this thing about jumping across creeks while riding- it scares me. I picture the horse slipping/sliding in in the soft mud as they land. (I saw this happen to a horse once and he was lame for a while afterwards, so that is where the problem started for me. He was the horse in front of me on a ride and we were crossing an irrigation ditch. He jumped it, slid a bit, and must have pulled something in his leg).
So that is why I decided to lead her across and put myself in danger. Probably would have been safer if I had stayed on. But all's well that ends well.