The pregnant woman who was sucker-punched for no apparent reason Thursday was so traumatized by the cruel attack, she’s too scared to set foot outside, she told The Post on Friday.

“I was just walking and somebody slapped me in the face, he pushed me and I fell down,” said Jannatul Ferdous, 34.

“I’m scared. My neck and back hurt,” she told The Post, refusing to step outside of her apartment.

The seven-months-pregnant victim was walking on a sidewalk in Bedford-Stuyvesant at 3:45 p.m. Thursday when the attacker stormed her from behind, she said.

“There were some security guards on the street who grabbed him, I don’t know what happened. I went to the hospital.”

Her unborn child was not injured, she said, adding, “The baby is OK.”

Ferdous had no clue why the violent jerk targeted her, she said.

“I don’t understand … The police asked me why he pushed me and slapped me. I don’t know why. He just did it.”

The attacker should be imprisoned, she said.

“He’s a bad guy. He should be put in jail,” she said.

The pregnant woman was knocked out cold on the ground by the punch. The man behind the attack was a Brooklyn man named Willie Stephens, 33. Officers found Stephens three blocks away and arrested him. The alleged assailant, who does not have a criminal record, was charged with felony assault in the attack.