I recently bought a saddle. My mom bought it for me, actually. I'm currently working with a PoA mare, but the saddle is an 18 inch!!! It was very cheap and needs work. I don't know how to make it a better for her. I'm nervous that she'll buck me off because she has too much pressure on her kidneys. She also has a tendency to buck at a canter. Will a riser pad help?? Please respond! IM DESPERATE!!