The actress took the director's chair for new movie In the Land of Blood and Honey, a self-penned film about a love affair between a Serbian soldier and a Bosnian woman.
But she was so stressed about testing her talents on the other side of the lens, she suffered a meltdown in front of her partner Pitt.
During an online Marie Claire interview Jolie said: "I had a complete emotional breakdown in the shower and Brad found me crying. I felt this huge responsibility and I felt very small. 'Who am I to take this on?'"
Jolie also revealed she only took on directing responsibilities by chance, adding: "I didn't plan to become a director, and I still have trouble saying I'm a director. I just wanted to tell this story and I ended up by default being the director.
"It was a pleasure, but I wonder if it would be a pleasure with another cast and crew, and a subject matter that wasn't so special."