Concerned

I went to the barn to ride today, but something was wrong with Harley. Thankfully, Kim was still there. While I was tacking him up he seemed as if he was falling asleep in the crossties. He even stumbled. Then in the indoor arena as I had finished tightening his girth and Kim came in and we were talking, when Harley almost fell. I got him walking, then mounted. We took a few steps and we could both hear him breathing. I got off and started walking him around. His nostrils were flared and I could still hear him breathing. He had never done that. We're concerned about colic. This changing weather is scary-it can be very harmful to horses. Kim got Pauline as I continues to walk Harley. He seemed to get a bit better. He was not hot at all (which is good). Kim brought in some hay and he did eat. We left him in the arena. I stayed with him for a while, walking him and making sure he didn't roll. About an hour and 45 minutes later I checked back in. Harley was in his stall drinking and eating hay. Kim called a few hours later-he's doing OK. We're praying it's not colic-he did poop in his stall-a good thing! We're not sure what's wrong, but hopefully he's fine. We'd be grateful for any prayers and healing thoughts you send our way. Thanks!