Thank you for the reply, I immediately brought her to the vet after posting this since I was so too nervous. Unfortunately they had to euthanize her so that was a very sad day but im glad she is no longer suffering.
My leo is young and I recently got her from a local pet store. (In hindsight now it is a pretty shady place). She we doing very well for the 3 months I've had her. But for the past few days she was acting lethargic and her tail was turning slightly more purple over time and got seemingly thinner...