[Peas let my pumpkins grow]

I have 4 khaki campbell eggs that were due to start hatching Friday (at 6am Lol ) but nothing has happened. Just a few wiggles on one or two eggs then nothing for hours. Trust me I've been watching them a lot, I obviously have nothing better to do with my time! I gave in this morning and put one in a glass of warm water and it had movement. I put it back with the x on top like when I took it out. Then I picked another and candled it for a second and it looks like the beak is in the air sack. I sprayed them with warm water for no reason other than a few people online say  they do that and put the lid back on. I'm concerned that they are taking so long. I know ducks are meant to be slower than chickens (my grandad used to do chicks but I only ever turned up as they were leaving the shells) should I be worried, are my ducks weak compared with most? I don't want to open them again just in case. I don't want to give up hope because they are still moving but is it likely that they will still have the strength after 2 days to hatch? This is my first attempt so I've got all the first timer worries!