A Queens barber charged with murder for allegedly of stabbing a teen to death with scissors in a dispute over a pair of $50 headphones claimed he acted in self-defense as he was held without bail Saturday.

“I stabbed him because he was trying to attack me,” Cedric Simpson, 34, told cops about the violence at his Laurelton barber shop Thursday that ended in the death of Carl Richardson, 19, according to court papers.