? on sore or touchy back

[DAldr94141@aol.com]

Hi. I've been going over and over something in my brain (which I don't claim 
to be very big) and I'm stumped. I've been worried about my high withered 
horse for some time. I ride in a Boz saddle. He was never sore until he shed 
out and I rode him in a 25 mile endurance ride. He had sore withers at the 
end of the ride and the next day he had a sore back. Well, things have come 
up and I wasn't able to ride hard for the next couple of weeks and I'm 
talking once a week for 2 1/2 hrs. not hard at all. Recently went a week and 
a half without riding and went to use a hard brush on my horses back. He was 
so touchy all the way down to past the croup. What's up with that? He's a 
pinto.  Is this considered a horse with thin skin? Sensitive skin? What if I 
go to ride in a CTR and they run their fingers down his back and he flinches? 
Am I s--- out of luck and have points taken off? Are some horses normally 
like this? I rode for 2 1/2 hours yesterday for 11 miles and he was fine but 
I used a gel pad underneath this time. Is it just because I rode the 25 
miles? 
Am I missing something besides brain cells? Thanks. Deb