Hoarse Barking, No Activity, Heavy Breathing

My dog is not well - I am very worried.

I noticed during couple days in a row she was trying to cough out something - by looking into her throat I saw nothing but she kept on doing and still does from time to time. Couple days ago her barking started sound hoarse, and today she is not active at all - literally laying down all day. Woke up only to go out, she pooped well, but peed only little, she also seemed to limp on her left from paw. Now it’s evening time and she’s breathing heavily.

I googled and description of Laryngeal Paralysis seemed to fit symptoms.

Is anyone had this kind of situation and know what can this be and how to treat it?

My dog is 4 year old female pit, not fixed.