Jessica Simpson is reportedly feeling "overwhelmed" with her weight loss regime.

The 31-year-old welcomed daughter Maxwell last month and has embarked on a plan to lose her pregnancy pounds as spokeswoman for Weight Watchers.

In Touch reports that Jessica has been set the goal of losing 50lbs in five months to reach her target weight of 130lbs.

But the publication claims that the fashion mogul is feeling "stressed" as she also tries to care for her newborn.

"She's so emotional," a friend told the magazine. "She doesn't want to go to the gym. She doesn't want to leave her baby. Sometimes she just starts crying. It's hard for her."

"She's consumed with the new baby. She and Eric are often up with Maxi all night."

But Jessica, who reportedly ate buttered Pop Tarts and other naughty snacks while expecting, is said to be desperate to get back in shape.

"She gets so upset," the pal added. "She wants her body back so badly, but it's beyond hard. But she wants to set a good example for Maxi. She wants to teach her daughter to have a healthy lifestyle."