Hilary Duff: Being a New Mom is No Joke!

Hilary Duff attends the book signing for her new book 'Devoted' at Barnes & Noble bookstore at The Grove on October 14, 2011. Credit: Angela Weiss/Getty Images

Hilary Duff has been a mom for just a week, and baby Luca is already keeping her busy!

"4 am...Sleepy eyed. Feeding baby..whew this job is no joke!" Duff, 24, tweeted early Tuesday morning.

"Luca fed! Mamma fed! Time to do it all again in 2 hours! Oh how life has changed! Lol In such a wonderful way :)" she posted on Monday.

And while the star and her husband Mike Comrie, who welcomed their first son, Luca Cruz, on March 20, are adjusting to being new parents, they definitely have some extra hands on deck.

"Haylie came over to make yummy kale salad and truffle devil eggs for din! I think it's more about her getting time with Luca but I'll take it!" Duff tweeted Monday evening about her sister Haylie Duff's visit.

Luca Cruz was a healthy 7 pounds, 6 ounces when he was born and is clearly the apple of his parents’ eyes.

"Welcome to the world Luca Cruz Comrie," proud papa Comrie, 31, posted to his Twitter the day Luca was born. "Can't express my feelings for you right now!"