the emergency vet suggested that we monitor her tonight and see how she does. she said swelling is normal, though it is a little odd that it's further below the incision. i thought it very strange how high her incision was, it's about the same level as the base of her ribcage, maybe 2 inches below her sternum, and maybe another two inches above her hoo hoo (2 inches doesn't sound like much, but she's only a 4-pounder). but regardless of where the incision was made, i'm assuming they had to do some operating further down, closer to her parts. it may be that she overdid it today and caused some inflammation.
if anyone else has experienced this, i would appreciate your advice. thanks! if a dog can cause this much stress, i can't imagine when we have kids.
at least kids can tell you what they're feeling most of the time