Is this a black Swedish duckling?

[ChickenMamaSarah]

After years of having chickens I was convinced to try adding a few ducks to my flock. We came home with these two of unknown breed and sex but I’m thinking the dark one looks like a Black Swedish. Does anyone know? Also, what’s that little puff on the yellow duck’s head? I don’t think it’s a crest because it’s just this tiny spot on the side of its head. They’re both three and a half weeks old.

 

[The Moonshiner]

Is it just me that's not seeing any pics?

 

[ChickenMamaSarah]

Is it just me that's not seeing any pics?

I had trouble attaching them to the original post. I added them in the comments. Can you see them?

 

[21hens-incharge]

https://www.backyardchickens.com/threads/is-this-a-black-swedish-and-what’s-this-puff.1237877/

Looks like there are two threads.I

I linked the other one so folks can go there and see the pictures.