In my country in Europe (and it's pretty much the same for the whole EU) if you have mild case , you are free to stop the quarantine 10 days after the onset of first symptoms (this goes 10 to 14 days depending on the EU country). The exact daily mileage may vary depending on severity of symptoms. Asymptomatic or mild symptoms can stop quarantine 10 days after onset without a need for any additional test, but if symptoms are more severe, the quarantine must continue. The quarantine must continue if you still have fever or troubling cough.