"I honestly had no idea, none whatsoever... But when he got on his knee, I kind of figured out what was going on," the reality TV star told E! News.
"As far as wedding stuff, I mean, we haven't even thought about or talked about anything. It's just been such a whirlwind. We need a moment to just kind of relax and figure it all out."
Kardashian added she has "no idea" how long they'll stay engaged before she actually walks down the aisle.
This will be the first marriage for West and the third for Kardashian, who had divorced music producer Damon Thomas in 2004 and NBA basketball player Kris Humphries in 2011. Seemingly because of Kardashian's relationship history, she told the website her wedding will be "whatever [Kanye] wants."