I got my first horse to train a couple years ago -everything was going really well with her and then a green broodmare threw me, she reared, bucked, then reared and threw me over the saddle where I rode at a canter for 80 feet before being able to get my foot unstuck from the stirrup. I woke up on the arena floor 5 minutes later with my mother in law standing over me not remembering much, I thought it was summer (it was christmas) I thought I was riding a different horse, I was so discombobulated.
It took me MONTHS to get my confidence back, I took some lessons and went slow, when I got nervous I counted, sang, had verbal puking of the mouth and babbled non stop to my other riding companions -anything to take my mind off of the scary. Suddenly one day I realized that I had just ridden through something spooky and wasnt counting anymore, I wasn't scared and I had built the trust back in myself as a rider.
Just take your time and go whatever pace is comfortable for you. It is really tough coming off and having your first hard fall -makes you question your own abilities. The fact is, everyone comes off at some point -even the best riders. That's all part of learning, no one becomes a great rider without a few falls in the process. :)