I don't know what to do

I have just put my ducks in their pen today. They have stayed in the water the whole time. I know this is normal but now it is dark and I went out there and made sure to show them the feed because I was afraid they didn't know where it was since when I hand fed them some they ate a whole lot. When I moved them over to it they ate a whole lot and their water turned foggy from the feed which it wasn't before and then I put them into the dog house but they came back out and made their way back in the water. One though had to walk the edge for a minute to, I suppose, a particular rock.
I went back out again and they were still in the water and it worries me that maybe they can't get out, only in. SO I put them back out thinking now that it was pitch black they might want to lay down on the towel they had in the brooder but yet again no. This time they just stood out preening. They didn't get back in the water or anything. I know that ducks don't go to "bed" the way chickens do but I worry since the area is new to them that they may not be familiar to them enough to go where they want or need to go to.

I know. I am a worrywart. But... I can't really help it so if anyone can give me some personal experience or opinions I would appreciate it.

 

I have rocks all on the outside and two on the outside. This morning they were still in the water but I pulled them out and they ate and slipped back inside. Just now when I got home and checked on them they were out of the water and about five minutes later when I walked back around they were back in the water. I actually reached for one of them and he hopped out and slid back in so I assume they just LOVE LOVE LOVE water. I don't think they have been in the doghouse unless I go stick them in there and then they simply stand there and then walk back out.