12:40 PM PT -- Young Buck's girlfriend admitted to cops she fired at least 2 shots during an argument with Buck that ignited over social media passwords ... according to the police affidavit.
The officer says Buck’s girlfriend, Lucresia Neal, told him Young Buck flipped over a large glass table in the home during the fight and grabbed her by her jacket and tried to throw her to the ground.
She told cops she escaped his grasp and went to the bedroom, where she retrieved a handgun from a gun safe.
Neal told police Young Buck ran into the room and she pointed the gun at the ground. She claims Buck saw the firearm and went down to the garage, where he started kicking a wall.
According to cops, Neal claims she went down to the garage, stood at the top step and Young Buck started to come up the stairs aggressively.
Neal told police she then fired a shot into the ground at the top of the stairs, and Buck started yelling at her to shoot him before jumping in his truck.
Next, Neal told cops she went outside to see if Young Buck had left, but he was still there and he revved the truck and started driving towards her.
Police say Neal claims she fired another shot outside and didn't think she hit anyone and insisted she wasn't trying to shoot Buck.
When the dust settled ... Neal told cops the damage to the home included 2 damaged TVs, paint thrown all over the bedroom, living room and foyer, plus a broken glass table.
Young Buck might have dodged a bullet ... we've learned his girlfriend got busted by cops after allegedly firing a gun while squaring off with him.
Law enforcement sources tell TMZ ... the G-Unit rapper and his girlfriend were involved in a domestic incident Tuesday at a home in Tennessee, and at some point, she allegedly picked up a firearm and let off a few rounds.