{{{Faith}}} don't be too hard on yourself over this. Kids are constantly trying new things and sometimes they ARE going to get hurt. It would be a different matter if he'd have been on a REAL bull... LOL Then you'd have some "splainin to do.
Please remember he's not the first kid to fall... or break a bone... or get laid up for a while over it. Just think of the cool story he'll have to tell his friends when he gets back to school! LOL
When I was 12, my parents let me buy my first horse. It was UNbroke and I had the job of breaking it. I ended up with a concussion and fractured skulll, and a 2 night hospital stay, but I finally got him broke. I also went on to break many more after. I have NO regrets and I sure don't blame my parents. Sometimes you just have to give them some space and pray for the best.
Have you ever heard of the Little Britches Rodeo Association?
http://www.nlbra.com/
It's a HUGE group that does rodeos with kids ages 8 - 18 nationwide. I know a few who've participated from my area. They have a ball. Blake might enjoy learning about them while he's laid up. Hang tough... You're a good mom when you let him try his wings.