Melissa Calusinski felt nothing when a judge sentenced her last week to 31 years in prison.

It was a stark contrast to the shock and horror that she said overwhelmed her when she was found guilty three months ago of murdering a Deerfield toddler at a Lincolnshire day care center where she worked.

This time, she was prepared.

"It's just a number to me, because I know I am innocent," Calusinski said from Lake County Jail, in her first media interview since her 2009 arrest. "I know that I'm going to get out of here, and I am going to do whatever it takes to prove my innocence."

Though Calusinski confessed to the crime on videotape, the petite Carpentersville woman, now 25, has since maintained that she was wrongly targeted for the death of 16-month-old Benjamin Kingan. Her lawyers have argued that her confession was coerced during a 10-hour interrogation, in part because of her low IQ.

Yet jurors at her trial in November apparently believed her admission and not her lawyers' claims that it was coerced. They convicted her of first-degree murder, rejecting a lesser charge of involuntary manslaughter. At her sentencing, Judge Daniel Shanes said he had "no doubt the defendant voluntarily made that (confession)."

As Calusinski prepares to be transferred to state prison to complete her sentence, her confession is one aspect of the case that her lawyers are focused on as they seek to win her a new trial. And although some observers question why anyone would confess to a crime they didn't commit, in recent years, defendants in two high-profile Lake County murders — Jerry Hobbs and Juan Rivera — were both cleared, despite both giving confessions.

In Calusinski's case, she had been interrogated for more than six hours before offering the first hint of culpability in the boy's death. Earlier in the questioning, she had suggested Benjamin might have injured himself because of his propensity to throw himself onto the ground during tantrums. Later, she offered that he might have hit his head on a chair when he accidentally slipped from her arms.

Over those hours, Calusinski's interrogators — Round Lake Park police Chief George Filenko and Highland Park police Detective Sean Curran — tried different tactics to elicit her confession, ranging from telling her that they were sure the boy's death was accidental, to telling her they were sure it was intentional.

Eventually, she agreed with a "yeah," after Curran suggested she had intentionally thrown Benjamin to the floor. Later, she recounted that version of events back to the investigators and used a doll to demonstrate how she mishandled the boy.

During her jailhouse interview this week, though, Calusinski said that she finally confessed because she was "very scared." She also said she was grief-stricken over Benjamin's death and was lacking sleep and food.

"I wanted to get out of there. … I was so isolated," said Calusinski, who added she's never been in trouble before besides a parking ticket. "I thought, 'I'll tell them what they wanted to hear so we can all go home.' I didn't think about jail. They made it clear I was going home."

After the confession, when she was told she was being charged, Calusinski said she immediately protested and claimed her innocence.

"I was like, 'You guys are making a huge mistake, I did nothing to him,'" she said. "They ignored me."

Calusinski said she's always been obedient and did what she was told. She said that might have led her to agree with police when they told her she was involved in Benjamin's death.

She also admits that learning was never easy for her and she was often the brunt of teasing and bullying because of it.

"I was kind of slow, but I did my best no matter what," she said. "If I said the wrong answer (other kids) would call me stupid. I learned to ignore it and do my own thing."

Her own thing turned out to be a love of art, the outdoors and children. Beginning her first baby-sitting job at age 13, she later became a nanny for five children before taking the job at Minee Subee in the Park nursery in Lincolnshire.

Despite everything, she hasn't given up her dream of being an elementary school art teacher.

"I love kids," she said.

And Calusinski said she continues to grieve for Benjamin, whom she said was "really happy. He was bold, he loved to play, he was always smiling. I had pictures of him on my cellphone."

She said she still doesn't know what happened to Benjamin that day but believes his fatal injury might have been caused by his habit of throwing himself backward to the ground, something she said he would do to get attention.

Benjamin's parents, Andy and Amy Kingan, did not respond to an interview request. According to a victims' impact statement read by Amy Kingan at the sentencing, she and her husband believe Calusinski caused their son's death and the heartbreak it brought to their family. Among the couple's other children is Benjamin's twin sister, who was also at the day care center when he died.

"Because of Melissa's actions, our children have been forever affected," Amy Kingan said. "The kids wonder if their teachers at school are going to kill them. There is no way to comprehend what Melissa has done to us, our family, our friends and most importantly little Ben."

For her part, Calusinski said she's taking things "one day at a time," reading, writing and drawing portraits of other inmates' children. She's anxious about being moved to prison, likely next week.

"I'm scared and worried because it is a new environment," she said. "But I'm going to continue to stay strong. I know I am not going to be in there for a long time."