Anyway yesterday I was brushing him and noticed he was sore in his back. I ran my fingers down his spine and pin pointed exactly where he is sore. It is near the end of his spine. When I looked down his spine from his front I noticed that the end of his spine seems like it is curving to the left slightly. He was sore on both sides of his spine yesterday and then today he was slightly sore on the left side but more sore on the right.
He is still moving around the field fine. He walks, trots, canters and even threw out some grow hops. But after I felt his back today and let him go he seemed agitated. He went and rolled and then jumped up and was tossing his head and being really weird for about 10 minutes. He then calmed down and went back to his old self. He also is grazing and eating his hay but only eating part of his grain. He was recently switched to a different brand of grain so it could be that he just doesn't like it. We just switched him back and will know tonight if that is what it was.
I have called the vet and chiro to come out and see him and will have them out within the week but was just curious if anyone had any ideas?