Ashlei,
If you are only interested in the horse for a horse picture, then the 1st one is exposed fairly well. The second one to my eyes on this monitor is now too bright. You are starting to loose the natural shadows.
The thing about the image overall is, there is a large range of tones - lights and darks (contrast) The time of day and perhaps the angle plus the fact that the horse is dark makes it tough but you can tweak it a bit in processing to make the overall image more pleasing. Not all photos have to be keepers, if you learn from one, then it served it's purpose to youas a photographer. (I sound like my dad lol) anyway
If you must keep working on this one, leave the horse alone and bring down the other areas a bit to help balance the tones.