Hi,
She definately looks kinda bloated - I'd be tempted to try the tepid bath again.
Hopefully it is just gas rather than anything more serious like the animal rotting in her belly.
What does the swollen section feel like?
Judging from the length of it I would say the rat was too big for her really - next time offering a second mouse after he has finished with the first might be a better idea.
How does she seem in herself?
Have you made sure your temps are ok as this is doubly important with larger meals I think.
dr del