We love Pictures so post some when you can. I haven't ever had Pekins but I have read many threads where they will pant so evidently they get warmer than other ducks.
At 2 weeks they can have a temp of between 75-80 in their brooder with a space away from the heat to cool off. What breed are your ducklings? I always start my ducklings thatIi brood myself at around 85* then lower temps 5* each week there after.
-60 that is sure a might cold. Brrr.