Help!

[buffytheduck]

I have just today found something strange in my duckling's behaviour. They bend their neck all the way down so their bill is touching their underbelly, their body spasms in intervals, (I'm not sure if they're just breathing but it's better to be safe than sorry) and they walk backwards. This is my first time taking care of a duck so I can use all the help I can get. Thanks, Buffy the Duckling

 

[Orca5094]

Are they maybe just preening their bellies? They are kind of awkward and lose balance when they're young doing this, so it might look strange at first. How old are they? Can you post a video of them doing it?