Is your cat currently nursing/recently had kittens? If so I would say something like mastitis, In which case you’ll need medication from a vet ASAP, as it can be incredibly painful and will lead to the mother preventing her kittens from nursing. If not you may want to take it in anyway as soon...
I have a ball python currently and it hasn’t seemed to effect him at all! I haven’t seen any negative reviews regarding dogs either, outside of that you may have to do some research. Worst case scenario get one that doesn’t have a label on it and say it’s an air freshener, maybe your roommate...
If the issues she’s having are stemming from stress/grief then I highly recommend a product like Feliway, you can order the diffusers off of Amazon but they essentially release hormones into the air that calm and soothe pets from stressors. It helps with spraying, urinating, etc. We had a cat...