OK so Tuesday everyone went to the vet, got checked out updates on shots and coggins tests, get home everyone is fine but my black QH is just walking around slowly. Then last night I noticed he's lying down upright not on his sides and just watches me as I walked by usually he runs up to me. So I checked him over and found a really long gash above his heel. There's no logical explanation as to what couldve caused it. Theres just grass and trees in his pasture. It really doesn't look that deep but I guess it hurts him to put weight on it? Any suggestions? Could there be any serious damage or am I worrying too much and he's just going to be in pain for a bit?