According to police, the gunman entered the Toyota dealership where Gallon worked in the service department before noon and shot her.
When police arrived they shot and killed the suspect.
But Gallon's mother Yuvonda Gallon says there are more questions than answers right now.
Gallon told KTVU it took more than six hours of waiting in a nearby police station for law enforcement officers to tell her that her daughter had been killed.
Gallon says she still does not have her daughter's belongings and that police have not told her how many times her daughter was shot or where.
While Gallon is frustrated, she's focusing her energy on her 7-year-old grandson, King, who is now left without his mother and father.
"That is saddening for me for real," Gallon said. "I told him that his mom and his dad was gone, and he laid his head back and said, 'No they're not.' He walked out crying, he's seen everyone crying."
Gallon said her daughter was extremely close with King.
King's father, who was shot and killed by police, had recently moved back to California from Atlanta.
Gallon said the two were not in a relationship and hadn't been for some time.
The two were co-parenting King.
"It's going to be hard for me hard for my family, of course, because she was loved by everyone. Everyone loved my daughter," Gallon said. "Her son is going to need therapy. I'm going to need therapy."
The family has started a GoFundMe to help raise money to pay for therapy for King.