He hasn't pooped except for last night and it was normal. He had a little diarrhea a few minutes ago and blood wasn't in it, but he did have another few spots of blood after. This morning he looked like he was trying to poop, but all that came out were small, bright red spots of blood. It's just clear blood with no stool in it. It's happened twice where he goes outside and this happens, the second time the blood was a little darker. I have 3 dogs and he ate their food last night, which isn't that same food as he usually has. My dogs haven't experienced any odd symptoms. He seems to still be somewhat energetic, but a little uncomfortable and whinny. He's about a year and a half old and a mutt. He's a small to medium dog, a little bigger than my 13 pound shih tzus. He ate last night, I don't think he ate all the food tho. I told his owners and they said that this hasn't happened before. He stayed in his kennel and didn't bark last night. I haven't seen him vomit and he's been drinking.