The 48-year-old actress said she struggled to find time for family, reported Femalefirst.
"I thought, I'm going to go into TV, be at home with my family. (But) I didn't see my family, and I never worked harder in my life!"
The Oscar-winning actress, who has a son Maceo, 20 months, with husband Olivier Martinez, and a daughter Nahla, seven, with ex-boyfriend Gabriel Aubry, said she was determined to continue breast-feeding her little boy despite spending long days on set.
"I was doing drive-by nursings every two hours. I was in over my head, the amount of scenes we shoot in a day," the "Monster's Ball" star said.