Tina Knowles Accidentally Posts Elevator Pic of Solange & Jay Z!

Tina Knowles has some big regrets today ... after posting a pic of Solange in an elevator with Jay Z, reminiscent of perhaps the singer's greatest hits.

Beyonce's mom immediately yanked the pic down, after realizing it brings back memories of the infamous 2014 beatdown in an NYC elevator.

TMZ broke the story ... Solange went HAM on Jay ... because she suspected he cheated on Bey.