It happened in less than 30 seconds.

In that instant, Jennifer Wertz thought about her three young children and her disabled mother she cares for at home.

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Then, Wertz pulled the gun from her pocket, readied it and shot the man pointing a gun in her face where she was working Monday at Circle K.

"I'm sick and tired of being a sitting duck," Wertz told KOAT. "We are not to chase. We are not to provoke. We are not to do anything. We just stand there and give them what they want and they leave."

Wertz was suspended by Circle K for two weeks for violating company policy by carrying a gun at work. She is likely going to lose the job she's had for five years. Her family set up a GoFundMe to help in the meantime.

"I'd rather be alive and have to find another job," she told KOB. "So I was thinking about it and I realized it was either shoot or be shot so I decided to protect myself."

Wertz, who was already feels unsafe walking to her car at night, was supposed to work until 10 p.m., and heard about a robbery at a nearby 7-Eleven earlier that day, so she made sure to take her gun.

She was not behind the counter when Ferron Mendez, 23, burst into the convenience store pointing a gun.

That's when Wertz fired, striking Mendez in the chest. He was taken to the hospital and is in critical condition, according to KOB.

Mendez is also the suspect in a robbery at a 7-Eleven that occurred earlier in the day, according to KOB. He is expected to be charged when he is released from the hospital, according to KOAT.

Mendez has no criminal history in New Mexico, according to the Albuquerque Journal. He had a Pennsylvania driver's license, but police did not know if he had a criminal history there.

Circle K did not comment about the incident.

Wertz, who has a concealed weapon license, won’t face charges, police said.

"I will continue to protect myself and my family," Wertz told KOB. "I understand the cops can't always be there. They're not always right around the corner. And we have to do something because these criminals are running our town. I've lived here nine years and they're literally running our town."