8 day old puppies. Do they sound healthy?

From what you are telling me they sound very healthy and active. You will have to look out for their gums turning white(which means they have worms). You will also have to watch the runt they are usually the most unhealthy. At a certain point in time, when they start to walk, you will have to start potty training them or else it is more difficult when they are a bit older. Try putting them on a schedule every two hours put them in the grass until they do their business. An alternative is using potty training pads.