Water belly? Internal laying?

[Liam McConkey1]

Hi all, my hen has been like this for nearly 2 weeks, still drinks, eats yoghurt, doesn’t move much at all (will post pictures), sits like a penguin, very skinny, the organ just under/behind legs is very bloated and is very soft and squishy? Comb and wsttle still has a good colour to it.
Can’t find any solutions, is the best option to put her down?
All help appreciated thanks

 

[DobieLover]

How old is she? She clearly doesn't feel good.

 

[Liam McConkey1]

How old is she? She clearly doesn't feel good.

Coming onto 3