A Putnam County Sheriff's Office news release says a deputy saw 31-year-old Jamie Gilt of Jacksonville behaving frantically inside the truck Tuesday afternoon and quickly realized she'd been shot.
The release says the woman told deputies her son accidentally shot her. He wasn't harmed and was reunited with family members. The Department of Children and Families will investigate.
Deputies say a .45-caliber handgun was on the truck's floor.
Gilt was taken to a Gainesville hospital, where she was in stable condition later Tuesday.
The truck, which was hauling a horse trailer, was partially parked in the road when the deputy stopped.
Authorities are investigating.
Copyright 2016 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.