Why is duck shaking and opening beak after swimming???

[OutbackQuackers]

3 year old female call duck has gone broody, and has been sitting on 14 eggs since yesterday.
So I've been letting her out twice a day for a 20 minute swim, and afterwards when I put her away she looks like she's struggling to breathe. She pants, shakes and opens and closes her beak for about 2 hours after swimming.

 

[ProudRedneck]

Sorry it has taken so long to get a response. Please take video of her when she is doing the concerning actions, it will help us determine what might be going on.

 

[OutbackQuackers]

Sorry it has taken so long to get a response. Please take video of her when she is doing the concerning actions, it will help us determine what might be going on.

I got her some vitamins and she seems to be doing better, I'll take a video if she has another episode.

 

[raingarden]

When ours does that I always imagine she is trying to talk like a human but just can't get the words out. A small treat takes her mind off of it.