"You play to win, but you never really expect to win the whole dang pot!"

Charles W. Jackson Jr. NC Lottery
Credit: North Carolina Education Lottery

Charles W. Jackson Jr. has played Powerball and Mega Millions with the same numbers twice a week for more than two years—the numbers from a fortune cookie given to him by his granddaughter.

And on Tuesday, those numbers finally came through, granting the 66-year-old a staggering $344.6 million Powerball prize and making him the largest jackpot winner in North Carolina history.

"You play to win," Jackson, a retired Cumberland County business owner, said during a North Carolina Education Lottery news conference. "But you never really expect to win the whole dang pot."

What's more, is that when he looked at his ticket for the first time on Tuesday morning—three days after the drawing—he didn't even realize what he was holding.

"I didn't see it all at first," Jackson recalled. "I thought I had only matched four of the five white balls. I thought that meant I had only won $50,000. I called my wife and told her, ‘I need to go to Raleigh. I won something!'"

It wasn't until he hung up the phone, that he realized he had won a lot more than $50,000.

"I decided to check again," said Jackson. "I saw the last number and thought, ‘I've won the whole thing!' I didn't know how much I had won until I googled it. I couldn't believe it! I still can't believe it. I'm numb."

WATCH: North Carolina Woman Wins Lottery Twice in the Same Day

The lucky grandpa reportedly opted for the lump sum payment, meaning he'll take home a whopping $223.3 million. He acknowledged that the after-tax winnings of $158 million is life-changing, though he doesn't expect it to change his life.

"It probably won't change much," Jackson said. "I mean, let me put it this way, I will still wear jeans. But I will probably buy some new ones!"

He also plans to donate a portion of his winnings to three charities

"I want to do something good," said Jackson. "I'm going to pay it forward and donate to St. Jude Hospital, the Wounded Warriors Project, and the Shriners. I always said I would if I ever won the lottery. So, I'm going to make due on that promise."