Yes I am aware, if it was a chick it wouldn't be an issue. You're talking duck egg which you're talking is coming 8 days early. While that's not a lot of time for people that's catastrophically soon to an animal with an incubation period of 28 days. If this bird really is hatching that early it cannot be developed enough to survive.
Now if you miscounted, or it started incubating sooner (like a window or something), ect that's a whole different story. That's why I was asking for photos. It'll be very clear in photos whether it was truly a "preemie" duckling or if something happened causing your days to be off.