Any insight on the -weirdest- accident ever?

Chisum is being weird. Surprise, surprise.

Saturday we went on a nice long hike. Mainly in creeks, but some grassland. He got good and tired...which was very, very nice but somewhat odd for him, actually. He's usually bouncing off the walls.

Sunday, he was still tired. We spent some time outside and it was warm (though he had access to water and shade while we worked) and he was still exhausted the rest of the day.

Sunday night he threw up in my room. Light green bile. Not unusual for him as he will occasionally get the hunger pukes, though they are fairly rare.

Monday evening he pooed and it was dark and bits were literally like tar. Black, soft, etc.

Monday night, overnight, he threw up 2-3 times in my bedroom. Dark green stuff with red bits in it that looked like blood. I saw it Tuesday morning and immediately got him an appointment with the vet.

He went to the vet and she came up with nothing. My mom picked up a stool sample from Tuesday and it looked fine. There were some dark spots in it but despite testing the vet wasn't sure what they were. Giardia was negative. They did a fecal float that was also negative. She felt around on his stomach and didn't feel anything that would indicate a blockage. He's eating and not throwing up during the day so she suggested some stuff like probiotics and Pepcid that would regulate him a bit and sent us on our way.

Last night, he didn't throw up. However, in the morning he did have a poo accident in my room. It was my fault - he had tried to get me up earlier and I ignored him. The poo looked totally fine, but when I went to clean it up I noticed that he had urinated as well. But not normal urination, like a puddle on the carpet. Drops EVERYWHERE around the room, single drops, like it had rained. Like he had been dribbling as he ran around.

This is super strange. Anyone have this happen before? I'm wondering if he was anxious because something did upset him in the middle of the night - he was running from window to window and barking - but he's done that before and this type of 'accident' has never occurred. onder: