No. Not the case. It sounds initially like she was developing an upper respiratory infection. If she is not sneezing or having congestion or nasal discharge today, it is not as clear cut. I would put that on the top of my list still, though. Without those symptoms, there are many, many things that it could be. Lack of energy and no appetite happen with pretty much any illness in cats. She may have swallowed something that caused an obstruction, a liver problems, a kidney problem, a toxin ingestion, pancreatitis, anemia, internal bleeding or trauma to name a few. My best advice is to get her seen by your nearest emergency vet. Cats are very good at hiding their illnesses, so when they start to show symptoms like this, it is usually more advanced than you would think. There really isn't anything that would be completely safe to give her at home, especially without knowing what the exact cause is. The only think would be 2.5 mg of Pepcid per 5-10 lbs of body weight. If she seems congested, try putting her in a room with a humidifier or in a bathroom with the shower on hot. Try to syringe her some water if you can. If still acting like this tomorrow, though, she absolutely needs to be seen. Please let me know if you have any other questions or concerns. Hope this helps.
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