STANFORD, California (AP) ― Serena Williams finally realized what happened days later, when she was allowed to get out of bed.

Williams said she was barely aware of how sick she was as she tried to play through a viral infection that caused her to lose equilibrium during a women’s doubles match with sister Venus at Wimbledon. It was only later, when she was able to clear her head, that she realized the seriousness of her situation.

“It was interesting and I was scared after,” Williams said. “I didn’t realize how I felt until later. In the moment I didn’t realize how sick I was. It’s weird but that’s the fight in me. I never know when to say when.”

Williams maintained that after three days in bed, she had already moved on and stopped thinking about it. She also ignored Internet rumors.

Looking comfortable and relaxed, the world’s No. 1 player said she’s ready to renew her pursuit of excellence on the court.

Williams meets the Czech Republic’s Karolina Pliskova on Wednesday in the second round of the Bank of West Classic. Pliskova beat Japan’s Kimiko Date-Krumm, 6-1, 6-3, on Monday.

“I’ve always felt good about this tournament and just being here,” she said. “This has always been a special place for me.”