Kaley Cuoco’s engagement to Ryan Sweeting, her tennis player boyfriend of three months, was a shock to the “Big Bang Theory” actress, for things weren’t going great in their relationship when he popped the question, Cuoco told Entertainment Tonight on Monday.

"He actually started a little fight with me and threw me off. I was like 'Oh my God, things aren't great,'” Cuoco said, opening up about her relationship with Sweeting the first time since she got engaged last week.  

But, later in the same day, Sweeting, 26, surprised Cuoco by popping the question with a 2.5 carat square-cut diamond ring, which has tiny diamonds along the band.

“He surprised me at the end of the night...he popped the ring out. It was amazing," said Cuoco.

According to reports, the announcement of Cuoco’s engagement last week raised several eyebrows considering the couple has been dating only for a few months. But, the actress told Entertainment Tonight that it feels as if she has known him for a long time.

"From day one I just knew immediately and it's been magic. We have all the same family friends. We grew up with the same people, we just never met. So I kind of feel that I've known him my whole life."

"I know that it seems a little crazy on paper," she added. "But it's what works for us."

The couple was first rumored to be dating in August after Sweeting was spotted with Cuoco at a horse ranch in Moorpark, Calif., made their official debut at the Emmy Awards on Sept. 23, and got engaged only a few days later.

Cuoco made headlines in July when she was linked to “Man of Steel” actor Henry Cavill. Sweeting is ranked number 532 on the ATP World Tour and turned pro in 2007, according to the ATP website.