Inset: Judah Chesley (Gilbert Police Department). Background: Police outside the Arizona home where Judah Chesley allegedly shot and killed his girlfriend (KTVK).

An Arizona man shot his girlfriend dead in a "drunken stupor" then called 911 and told them, "Well, now it's my ex," according to police. He also called his dad after killing the woman and recounted how he pumped a bullet "into her chin" but didn't know why or how, cops say.

"I don't even know what to do," Judah Chesley, 26, allegedly told a 911 dispatcher after allegedly shooting his girlfriend early Monday shortly before 1 a.m., according to a probable cause affidavit obtained by Law&Crime.

"My parents aren't even coming down," Chesley allegedly said about his mother and stepfather, who were inside the home where the fatal shooting occurred but had not witnessed the scene. "Everything in life leads up to this. I don't know what to do."

Chesley, who lives in Gilbert, told the dispatcher to "triangulate the location" of where he was early Monday, according to the affidavit. "It's not her fault," he allegedly said. "Don't blame her."

Chesley is accused of killing his girlfriend, who has not been publicly named by police yet, with a gunshot wound to the face before calling his dad. He allegedly phoned 911 after attempting to contact his father and admitted to being intoxicated.

"Ma'am, my ex, well, now it's my ex, woke me up in a drunken stupor," Chesley told the dispatcher, apparently referring to his own intoxicated state, according to the affidavit.

Officers arrived at the home and took Chesley into custody after coming into contact with him and observing blood on his hands and clothes. A semi-automatic Glock 9 mm handgun was found with blood on it near the victim.

Investigators spoke with Chesley's dad, who said Chesley tried to call him multiple times.

"[Chesley] didn't know how it happened, but a bullet went into her chin," the affidavit says, citing his dad's statements to police.

Chesley's father alleged that COVID-19 lockdowns "deteriorated" his son's mental health, but his son refused to "go see a mental health professional," according to police. Chesley's mother and stepfather, who according to the affidavit were asleep when the shooting occurred, also spoke to investigators and said he owned firearms and was known to get "aggravated" about things.

More from Law&Crime: 'Continued to shoot her lifeless body': Man who emptied 9 mm into ex-girlfriend as their baby watched, reloaded and continued firing hears fate

"There's days where it just seems like, if he gets upset, like it kind of sets him off and he doesn't think right," the affidavit says, citing accusations made by Chesley's mom and stepfather.

One of the girlfriend's family members spoke with police and said that she and Chesley had gotten into "numerous" arguments in the past. In one prior incident, Chesley used a Taser on the victim, the relative said.

Chesley was booked on a charge of second-degree murder. Court officials told Law&Crime on Tuesday that prosecutors had not yet formally filed charges.