It's indeed very tiny and I'm somewhat blind...
But from what I could see you are not aligned (shoulder/hip/foot): your legs are very forward. Also your arms are straight and move quite a lot on trot (as already suggested bend the elbow and keep them close to the body). Nice horse BTW.
"Life isn't about waiting for the storm to pass: it's about learning to dance in the rain..."
"When we are no longer able to change a situation - we are challenged to change ourselves."
"How people treat you is their karma; how you react is yours."