Question about duckling behaviors.

[Decorum]

So, recently I got a baby duck. It was only three days old and I had to teach it how to eat, drink, etc. I just have a few questions about it's behaviors.
-Why does it burrow in the crook of my neck? It does this whenever I put it in my lap.
-Why does it cry when I leave the room?
-Does it still have the ability to imprint after it's already imprinted on it's previous mother?
-Why does it only ever fall asleep when I'm petting it?
-Why does it sometimes start cleaning itself or lightly pecking my hand when I pet it?

If you can answer any of these questions, I would much appreciate it.

 

[Kessel23]

It sounds like he is imprinted on you. Ducklings will try to burrow into the crook of your neck if they are cold.

 

[TheTwoRoos]

It already has imprinted on you,that is why it cries when you leave the room.It burrows for comfort,as it would burrow under its mother.Your its comfort that’s why it falls sleep when you pet it.

 

[Miss Lydia]

It also needs a friend. https://www.backyardchickens.com/threads/why-you-shouldnt-keep-just-one-duck.1228573/