Bradley Martin, 50, told a man's murder trial that there was an argument in the bedroom of a home he shared with two other people on March 30, 2013, and he went in to intervene.
"I turned to go to the bathroom and next thing my ears were ringing," Martin said.
"I realized that half my body had gone numb. I looked down at my chest and seen blood pouring out of my chest."
Martin told a B.C. Supreme Court jury Wednesday that after seeing the blood, he realized a shot was fired and looked around to see John Koopmans sitting down with a gun on his lap.
Koopmans, 51, is on trial for two counts of first-degree murder and one count of attempted murder in the shooting that injured Martin and led to the deaths of Robert Wharton, 43, and his girlfriend, Rosemary Fox, 32.
Martin told court that on the day of the shooting he arrived home from work at around 1 p.m. and fell asleep in the living room.
He said he awoke that evening to the sound of his dog barking, and watched as Fox let Koopmans into the home and led him to Wharton's bedroom.
Martin said about five minutes later he heard the three arguing about a break-in at Koopmans' home. He said Koopmans was blaming Wharton for the event, but Wharton was "vehemently denying" any involvement.
Martin said he considered all three to be his friends and walked into the bedroom to help settle the dispute.
Moments later, he went to get Koopmans a cloth from the bathroom to wipe some dirt off his face, and the shot rang out, Martin said.
He said he fled the house and took cover in the yard, before making his way to the road, where he flagged down a passing motorist who called for help.
The driver, Lisa Haigh, has testified she didn't want to let a "frantic" Martin, who wasn't wearing shoes or a jacket, into her car for fear of her own safety.
"He was saying that somebody was going to kill him, somebody was going to shoot him, he needs help," Haigh said.
RCMP Sgt. Joanne Skrine told court earlier Wednesday that she took a statement from Martin at Kelowna General Hospital three days after he was shot.
She said he seemed paranoid about police because he "had some negative dealings, in his mind, with the RCMP."
Martin has told court his bullet wound has resulted in a loss of strength and mobility, plus emotional harm.