You know ... I had BB spayed in December and she looks like she's got a soccer ball inside her! In fact, I'd been looking at her and wondering if there were a problem, but she allows me to poke/prod and pick her up without any complaints so she isn't in pain like she'd be if it were an infection or FIP.
It's just her abdomen, her limbs and body feel fine, not overly-fleshy. I've wondered if her (unknown) years of having kittens damaged her abdominal muscles and if that's just how she's gonna look, or if she'll eventually tone-up, or if it is gas?