Milano explained that she had been sick for two weeks. She wrote that "everything hurt," she lost her sense of smell, couldn't breathe and "couldn't keep food in me."
"I basically had every Covid symptom," she wrote alongside a photo of herself wearing an oxygen mask. "At the very end of march I took two covid19 tests and both were negative. I also took a covid antibody test (the finger prick test) after I was feeling a bit better. NEGATIVE."
After still having lingering symptoms -- "like, vertigo, stomach abnormalities, irregular periods, heart palpitations, shortness of breath, zero short term memory, and general malaise," she wrote -- she went to get another antibody test. After she got her blood drawn, she tested positive for antibodies.
"I had Covid19. I just want you to be aware that our testing system is flawed and we don’t know the real numbers," she explained. "I also want you to know, this illness is not a hoax. I thought I was dying. It felt like I was dying."
Milano concluded her post by writing that she will be donating plasma in hopes that it might save a life. She also reminded people to "take care of yourselves. Please wash your hands and wear a mask and social distance."
The former Charmed star's post was quickly filled with well wishes and messages of support from her friends and followers.
"Who’s the Boss? was a very progressive show. A divorced mom, who owned her own business and had a free-spirited mother who made sex jokes, who hires a single dad to be her housekeeper," Milano said in a statement given to ET on Tuesday. "We were really a modern family in the 80’s. We look forward to making the sequel as thoughtful, smart and relevant to the times today. And make people laugh at the same time."