NASHUA, N.H. — A New Hampshire man trying to convince a jury he was insane when he took part in a machete and knife attack that killed a woman and injured her daughter testified Tuesday that he felt nothing during the attacks and a flood of relief afterward.

Christopher Gribble, 21, detailed the attacks and bloody crime scene for jurors in a monotone that didn’t waver, even when he described plunging his knife into Kimberly Cates’ throat.

He has admitted killing Cates and trying to kill her 11-year old daughter, Jaimie, in their Mont Vernon home. But he claims he is not guilty by reason of insanity.

“Back in the car I remember feeling like a huge weight had been taken off my shoulders,” Gribble testified. “I didn’t feel like I had to do that anymore – kill someone.”

Gribble testified he had fantasies about torturing and killing his mother since about the age of 14. He also said he would compose “kill lists” of people who had snubbed or angered him. He said earlier Tuesday he used music and imagining a calm place to keep his urges in check.

He said he had no feelings about the victims during or after the attacks.

“I had no connection to those people, so maybe it didn’t matter to me,” Gribble said.

For eight hours over the course of Monday and Tuesday, Gribble answered his lawyers’ questions. Prosecutors have yet to cross-examine him and seldom objected during his rambling testimony.

Gribble told jurors the bloody crime scene he left behind looked just like a crime show episode. He described the severe cuts to Cates’ upper body and the bone protruding from her sliced arm. He said he does not recall flinging Jaimie Cates into a sliding glass door, but described her lying still in a large pool of blood with “little bloody footprints” all around her.

One female juror wept as Gribble described how he plunged a knife into Cates’ neck and had to adjust its angle to be sure he severed an artery.

Steven Spader, who wielded a machete during the attacks, was convicted of murder and other felonies in November and is serving two life sentences without possibility of parole.

Gribble said that Spader kicked Jaimie Cates a couple of times before raising the machete above his head with two hands and bringing it down on the child’s head. “I knew he was trying to cut her head off,” Gribble said nonchalantly.

“He was standing there panting and it looked like he was in a rage sort of thing,” Gribble said of Spader. “He was completely out of control. I was more precise. I was very controlled.”

Gribble testified Monday that his mother, Tamara Gribble, abused him physically and emotionally. She denies it.

Earlier Tuesday, Gribble testified that he was devastated when his girlfriend broke up with him the week before the Mont Vernon home invasion. “I felt like nothing mattered anymore. It broke me completely,” he said.

But he and his girlfriend got back together the day before the Oct. 4, 2009, home invasion and had sex just hours before Gribble, Spader, Quinn Glover and Billy Marks broke into the Cates’ home. Prosecutors say Glover and Marks were in the house but played no role in the attacks. Both have plea deals with the state. They testified against Spader and are expected to testify at Gribble’s insanity trial as well.

Gribble’s self-control will weigh into the jury’s deliberations on whether he suffered a mental disease or defect and lacked ability to control his impulses.