We broke the story ... Octo is smoking weed again after obtaining a medical marijuana card. Her friends says she's playing with fire because she's had drug addiction problems that could endanger her 14 kids.

Octomom friends say she's acting like she did last year, when she was videotaped inside a hotel room with her manager. She's off the rails, wearing a onesie as she cackles hysterically, cradling a drink. We're told the video was shot in the throes of her substance abuse problems ... before she went to rehab.