The mother of the alleged Club Q mass murderer was arrested just after the shooting ... for going ballistic in her apartment and then going off the rails with cops.
Laura Voepel was allegedly screaming at the top of her lungs at 3:30 AM ... 3 1/2 hours after authorities say her son took a rifle and killed 5 people at the LGBTQ nightclub and wounding 17 others.
According to official documents, cops were on scene at her apartment when she was "warned multiple times to stop yelling or she would be arrested for disorderly conduct."
Cops say she continued her rant, and when officers tried to arrest her she became combative and physically resisted them.
Voepel was charged with resisting arrest and disorderly conduct.
Her son, Anderson Lee Aldrich, is facing 5 counts of first-degree murder and 5 counts of bias-motivated crime causing bodily injury.