Karrueche had no idea Chris Brown was a dad until moments before TMZ broke it

Men can make women run mad sha. Almost looks like Karrueche used her hands to pull out her front hair after finding out her man of 5 years fathered a child while in a relationship with her. According to TMZ, Karrueche found out about the baby almost at the same time we all out found out.

Karrueche Tran was in the dark ... blindsided by Chris Brown's baby news just moments before TMZ broke the story. We're told Tran had absolutely no idea her boyfriend was a daddy -- much less a daddy with a baby mama with whom she partied.

Our sources say Karrueche and Brown had a blowout fight a week ago and weren't speaking, but he tried calling her after the story broke ... she did not pick up.  

DNA tests performed in the last week show conclusively ... Brown is the father of a 9-month-old baby with a former model named Nia. We're told he and Nia aren't romantic but they get along fine, and Chris has made some sort of financial arrangement with her.  

As for Karrueche ... we're told she's actually relieved, because it now gives her a clean, permanent out.