I am sorry this is so worrisome!! The pictures are good and you know your kitty best. The pictures don't alarm me for what that is worth but Taz is not my baby either. I have tried studying my own kitties in this way and only have a few things I notice: Robbie & Lizzie both eat really fast and are growing too fast side to side. So, I do sometimes see the changes during the day. Eliot is very thin and has ribs that stick out sometimes if I look from the top. Our very first female was Emily and when she was about 1 or so, I took her to the vet thinking she may have a tumor and it turned out to be nothing but that girly pouch that females can sometimes get after the spay. My vet and receptionist got a bit of a chuckle - but I was relieved. I know you are worried and I would be as well. Maybe the vet will contact you today? If not then Monday right? That belly fluid possibility would scare me - because some here (kimlovescats & others) have been through that heartbreak of FIP and I always keep that in the back of my mind too - probably WHY I notice the kitty silhouettes from the top.

(((hugs)))) to you and prayers that your mind can be peaceful very soon. Hopefully all will be well.