Poor pup! My puppy loves running around our pool too while we are playing in it. Thankfully that hasn't happened to him but I will be careful with that from now on. The worst thing that happened was when he got so excited he fell right in. We found out he can swim though! It didn't phase him a bit, we got him out and he went right back to playing! Silly dog. He hasn't learned to love swimming yet but he will get on the top step to cool down when it is hot. The Epsom salts sound like a great idea. And I hope he heals quickly so he can get back to playing!