My go.maybe it just me but lengthen your stirrups a bit. They look a bit to short even for jumping. Your jumping slightly a head of your horse aswell.
Your also jabbing your spur right into the horses side. So idk maybe your gripping almost with the back of your calf or heel?.. or trying? I cant really explain what im seeing lol! Someone else can clear this up maybe
I love that horses markings and coloring very cute! With minor adjustments you guys are gonna look amazing!