Thank you for your patience. These symptoms in Nala are very concerning. As you can probably appreciate, there are quite a number of possible causes for your girl's symptoms, however for these symptoms to have occurred all of a sudden during the night in a young cat, I would be most concerned about a toxicity (hopefully there isn't anything she could have gotten in to), trauma (from falling from a height), an infectious issue, or an allergic reaction (such as from a bee or bug bite/sting) - to name a few potential causes. Whatever the case, the fact she is so lethargic and weak is definitely a big concern right now. If she seems to be very lethargic, painful and/or distressed, then there is no question that you need to get her seen by your local vet straight away.
If you can't get her seen right now, then please keep an eye on your girl's mucus membranes, capillary refill time and respiratory rate as follows (do be careful that your girl doesn't try to bite you):
Mucus membranes - flip her lip and look at the color of her gums. They should maintain a nice salmon pink color. Get her to your local Vet if they appear white or very pale pink, or if they are a dark deep red color.
Capillary Refill time - this measures blood perfusion and test this by putting your thumb on her gum to apply pressure. After you release your thumb you will see the gum blanch. Capillary refill time is the amount of time it takes (in seconds) for the gum to return to a healthy pink color from the blanched white color. If 2 seconds or less don't worry - if it is taking significantly more time, again - off to the Vet.
Respiratory Rate - if she is continuously panting or open mouth breathing at all today, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
In this instance, these isn't a lot you can do from home. Please don't be tempted to give her any human pain medication as this is mostly toxic to cats and would worsen the situation. Have a good look around your home to see if there is anything Nala could have gotten into overnight. As above - please try and get her seen by your local vet in the next hour or so if you can. It is always better to be safe in these situations of sudden weakness and lethargy. I hope all of the above makes sense? If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!
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