Derek Vernon Medina, 31, is being held in jail without bond on first-degree murder charges for allegedly shooting and killing his wife Jennifer Alonso, 26, on Thursday morning.

Medina appeared before a judge Friday. He wore a padded gown -- given to those inmates on suicide watch -- and is being held in the psychiatric ward of Miami-Dade County Jail.

The couple got into a verbal argument around 10 a.m. in their South Miami home.

The argument lead to Medina shooting and killing Alonso in their kitchen while Medina's 10-year-old daughter, from another woman, was still inside the house. Medina said he armed himself with a gun only after Alonso began punching him, and then shot her while she wielded a knife, according to court documents.

Medina is likely to claim self defense, according to the Miami Herald.

Medina took a photo of his dead wife and then posted it on Facebook, along with a confession.

In the photo, Alfonso's lifeless body laid twisted, knees bent backward. 

After the shooting, Medina changed his clothes and drove to his family's home where he told his father, Derek Medina Sr., that he killed his wife. At no point did he ever attempt to call 911.

According to police, Alonso told her husband she was leaving him right before she was shot and killed.

Neighbors who spoke to the Fox News affiliate in Miami, WSVN, said they heard screams coming from the apartment. "Kind of like a desperate person, and there was just a lot of yelling,"

Moments later, the neighborhood flooded with police, officers discovered Alonso's body on the kitchen floor and they escorted the late woman's uninjured, 10-year-old girl from the home.

Medina drove to South Miami police headquarters to turn himself in.

Derek Medina Sr., the suspect's father, said his son rushed over to his home at around 11 a.m. and admitted to shooting his wife. "My son basically said that his wife picked up a knife, and they had a big fight, and he shot her,"  Medina Sr., told WSVN. "And all he said was, 'I need to go to the police.'"

Medina Sr. said, "I'm still in shock. Just in shock right now."

Alonso's stepfather remembered her as a beautiful and kind-hearted person. "She is a gem in her own way. Loving, anything you can think of on a positive basis. She is all of that. It's just sad that she is gone, but I can only say she was a beautiful woman. A beautiful girl, a daughter."

Medina PDF

An 'Odd Man' Neighbors Say

Medina's neighbors remember him as an eccentric and peculiar man. 

"He was very odd. So, when we saw the news I wasn't completely surprised because I always thought he was a little unstable," said neighbor Anne Swary. "She [Alonso], in my opinion, behaved as someone who was maybe a little afraid of her husband."

A Troubled Marriage

Problems between the now jailed Medina and his deceased wife were well documented. Medina Sr. said:  "She was a beautiful woman. They always had some problems."

Marriage records show Medina and Alonso married in April 2012, got divorced, only to then remarry months later.

Alonso's former boss at a West Miami-Dade Denny's restaurant told the Miami Herald that Medina was an "extremely jealous" man who had hit her in the past.

“She would be bruised up,” said Amanda Cooper, to the Herald. Cooper said Medina was "controlling." 

A YouTube Fan

Medina had a very active YouTube Channel posting everything from his listed appearance on USA show Burn Notice, to punching a karate bag -- extremely violently, singing along to "Ain't No Sunshine" in his car.

An Author

Medina authored six online 'self' help' books, with extremely long and convoluted titles.

He even has a preview video for his new self-help books, including one video where he gets his grandmother to read the titles aloud.

Here are some of these book titles: 

"How I saved Someone's Life and Marriage and Family Problems Thru Communication."

"Humans Who Are Gifted And Can See the Supernatural Spirit Ghost World We Live In Called Ghost Haunted Adventures."

"How a Judgmental and Selfish Attitude is Destroying the World We Live in Because the World is Vanishing Beneath Our Eyes."