Rambo has been doing much better.
That night I got home, I wanted him to drink some water. So I put some in the palm of hand till he was drinking out of his bowl. He also ate a little bit of his food. By the next day he was back up and running around. Being the little man that I love!!
I did speak to the vet and she stated that since I live by a lake he could have at some dog poo (eww

), but I should watch him for the next couple of days.
Thanks for all the suggestions and help.