Dude, about your dog... I don't know where you live but it sounds like the heat. Nothing serious ^^ You could try putting some ice cubes into his drinking water or try to see if he'll eat them, keep him in the shade and if you have a fan keep him near to it. :) I hope he gets better
It’s actually been in the low 70s here all week. We’re very careful about keeping him cool in the heat, though.