My worst fall was many years ago when I was 10 and riding my QH named Blaze. He was about 15hh and I was a midget on him but he was so calm and laid back my mum just saddled him up and let us go. So I was riding the trail around our paddock when a neighbours kid started throwing rocks at Blaze, one got him on the rump and he was not happy, he took off with a buck back towards the house and I just went up and then down, he wasn;t under me and I went smack on the ground. I was winded so bad and bruised my tail bone. I couldn't even cry when I was winded :( it is so painful, I will never forget it :(
As for the most embarrassing fall, I was at a rather big show in the pony derby class and there was about 20 ponies and we were jumping about 80cm. Two pinto's had gone before me, one was my sister, and the riders both fell. So I go in and the commentator made a joke about pintos being bad luck so I was rather determined to get around and I got to jump four, Kai skidded to a stop and I went flying over and landed smack on my face on the other side, butt in the air. Kai cantered out of the arena, jumped the side fence which was about 1 metre and waited for me in the warm up ring while I walked out to a laughing crowd!!!