Hi, I've only been riding since last fall. When I started out riding everything seemed to come quickly and naturally. Then at the end of June I was working on the canter, and my instructor let me cantor off the lunge line for the first time around the rink. Everything was fine the first few times around, then my horse got feisty and yanked her head forward aggressively, and due to my own poor position and inexperience, I went right over. Ended up landing on my head with a concussion that kept me out of work for a week.
After a month off I went back to my lessons, and things seemed to be going fine. Then last night we were again working on the canter. When we worked in a small circle at the top of the ring everything was fine. My instructor gave me the green light to try a loop around the full ring. 3/4 of the way around I felt my horse transition to a full gallop. I tried to slow her down, but she refused and started bucking. I held on through 2 bucks, but on the third one she sent me sliding forward down her neck. I hit the ground on my butt and back (thankfully not my head!), and the horse stepped on my shin before immediately backing up (I'm only slightly bruised thanks to my boots).
I got back on a few minutes later, and we put the lunge line on the horse. I did a few turns at a trot, then a canter. We stopped and repeated. The horse tried once more to transition from canter to gallop, but I was able to retain her this time.
My instructor says that while people have fallen from her horse before, she's never seen her horse buck off a rider. Normally she lets even her youngest riders learn on this horse, because she's typically very calm and hard to get excited, though she is only 6 years old.
My questions to the forum are:
1) Do you think maybe I'm doing something that is encouraging the horse to get excited and act up? My instructor says my positioning is great, and I doubt I'm giving too much leg, but I am open to hearing what you might think.
2) What should I have done in this situation? I will discuss it with my instructor, but I am wondering if you guys have any thoughts on what to do when your horse takes off/bucks like that.