The Bronx student convicted of fatally stabbing a classmate and injuring another got a 14-year prison sentence on Tuesday — as he apologized for the “damage” he caused and called himself a “monster.”

Abel Cedeno, now 20, has claimed he carried out the gory 2017 classroom stabbing at the now-shuttered Urban Assembly School for Wildlife Conservation after years of homophobic bullying.

Judge Michael Gross did not dispute that Cedeno had endured torment.

“I believe you paid an emotional price for the repeated acts of being bullied, which undermined your self-image and psychological well-being,” Gross told Cedeno in a packed Bronx Supreme Court courtroom where Cedeno’s family, both victim’s families and the surviving victim were present.

But, he said, “Your history is not an excuse for what you did.”

“That classroom was turned into a nightmare that day,” said Gross before he sentenced Cedeno to 14 years in prison for manslaughter, eight years for assault and 90 days for criminal possession of a weapon.

The sentences will run concurrently and will be followed by five years of post-release supervision.

Cedeno’s victims weren’t just those he stabbed “but each of the 20 students who witnessed the attack and suffered trauma that will be with them forever,” Gross said.

Cedeno addressed the court before his sentence was handed down, saying, “Everything that happened that day almost two years ago, I’m not the same person as I was two years ago.

“I’m sorry for the pain and suffering I caused on the family,” Cedeno said. “I’ve been sorry about everything, for the damage I caused for hurting two families.”

He continued, “I call myself a monster. I call myself a murderer for everything I’ve done, everything that happened . . . I feel horrible every day. I wish I could take it all back.”

Cedeno was found guilty on all counts back in July following a roughly two-week non-jury trial.

A then-18-year-old Cedeno fatally stabbed 15-year-old Matthew McCree in the chest with a switchblade at the East Tremont school on Sept. 27, 2017 after he flew into a rage when a paper ball or pencil was tossed in his direction.

Cedeno, who claimed self-defense, knifed then-16-year-old Ariane LaBoy five times when LaBoy tried to intervene.

“Seeing what Abel did to my nephew made me lose faith in everything I believed in,” McCree’s aunt, Lacey Providence, said in a victim impact statement. “Matthew was lifeless, drenched in blood with a cut so deep that I could see his ribs.”

LaBoy’s mother, Felicia, also delivered a victim impact statement, saying that her son “lost his best friend, his childhood and his joyful nature” after that September day.

McCree’s mother, Louna Dennis, let out a blood-curdling scream as LaBoy’s mom spoke. Dennis left the courtroom but returned for the sentencing.

Speaking to reporters outside court, Dennis said Cedeno’s apology was not “sincere.”

“That was not an apology, because an attorney was telling him what to say,” Dennis said, adding that she was “OK” with the 14-year sentence. Prosecutors had sought 30 years on a maximum sentence of 50.

Cedeno’s lawyer, Christopher Lynn, called his client’s sentence “excessive” and said he plans to appeal it.