Pet ducks laying eggs?

Hi I have some pet ducks that I've had for about a year. About last week they began to mate, but i though nothig of it, today I went into the garage (where they stay at night) and i fouund one egg. The eggs has not been in there for more than 12 hours. The hen was not sitting on it. idk if it's fertil. so i took it. The egg is really round i didn't think ducks layed round eggs. It looks like a ping pong ball, but i'm 100% sure its one of their eggs, i'm not sure if it's my pet mallards eggs or my pekin duck's eggs. i think it's mallard bc they're really small. i took the egg into the house bc Willma wasn't sitting on it. I'm thinking about just tossing it. but is there a chance that it will survive? it's been in the 60 degree F garage for like 12 hours, it's round, and it's a firs time mom's eggs. what do you guys recomend? i would love them to have a little family. but idk what to do with the egg. she doesn't seem to want it/ any advice? i'm going to try to incubate it for like 7 days to see if it's fertil (candle it), and if not i'll toss it. but do you guys have any advice in the mean time? thanks!