An Ottawa woman who won last week's $48 million Lotto Max said she bought the ticket "on a whim" Friday while picking up groceries.

Tina Ferrone said on Tuesday she had never played Lotto Max before, and when she checked her ticket Saturday at a Shopper's Drug Mart in the Ottawa neighbourhood of Kanata, she was in shock.

OLG $48M winners Tina Ferrone Kanata

Tina Ferrone and her husband Liam of Kanata, Ont. picked up their lottery winnings on Tuesday. (CBC)

"I thought it was $48,000 at first, I couldn't process what was happening," she said while picking up her prize in Toronto on Tuesday.

When she found out what the ticket was really worth from a lottery agent who called the store, she handed the phone to her husband, sat down and hyperventilated.

Her husband Liam, who was diagnosed with cancer in January 2012 and has been out of work as he undergoes chemotherapy and stem cell treatment, was calmer about the news, Ferrone said.

"It's been a long road, we didn't expect to get something like this," he said. "After all the dips we get a big boost."