Woohoo! This is wonderful! Like said, I believe the reason so many people automatically jump to 'physical pain' when giving advice here is because of one or more of these things -
* They can't see the horse actually doing what it is
* They don't know how to fix the problem, just want some more posts
* They can't judge the horsemanship of one over the computer, so they don't know if this person can tell the difference between bad manners or ouchie. <= Biggie for me.
But it is ridiculous that people excuse things for pain - I fell into the trap some years ago. I thought my horse was bucking rearing, bolting, etc. because he was in pain. We had a trainer come in, tell me straight, put that horse in line, made ME put that horse in line, and we never had another problem. Looking back at the signs he gave (we sold him a while ago) I realise now that that horser was just flat disrespectful. Period.
Now I understand it is pain sometimes. Cowboy started throwing his head and pinning ever so often undersaddle. This was not him, at all. I put an extra pad on his back, assuming it could be his ridiculously high withers, and never had the problem again. There is a happy medium - you have to find it.