Natalie Portman returned to her alma mater to give an inspiring speech at Harvard College's Class Day on Wednesday, May 27, and revealed her time at the university had not all been an easy ride.

Encouraging the soon-to-be departing students to use their youthful enthusiasm to take risks and carve their own path in life, the Star Wars actress spoke candidly about her own time as a student, and her constant questioning of her own self-worth.

"When I came in as a freshman in 1999, I felt like there had been some mistake," she told the gathered crowd. "That I wasn't smart enough to be in this company, that every time I opened my mouth, I would have to prove that I wasn't just a dumb actress."

As she adapted to the academic rigors required to get by at Harvard, she then found herself struggling with "dark times," as she progressed into her sophomore year.

"It's easy now to romanticize my time here, but I had some very difficult times here too," she admitted freely. "Some combination of being 19, dealing with my first heart break, taking birth control pills that have since been taken off the market for their depressive side effects, and spending too much time missing daylight during winter months led me to some pretty dark moments, particularly during sophomore year," she continued. "There were several occasions I started crying in meetings with professors, overwhelmed with what I was supposed to pull off, when I could barely get myself out of bed in the morning," she added.

But the Oscar winning mom-of-one learned some important lessons during her academic experience and carried those lessons with her into her acting life.

"You can never be the best," she told her eager audience. "The only thing you can be the best at is developing your own self. Make use of the fact that you don't doubt yourself too much right now. As we get older we get more realistic, and that realism does us no favors," she added.

Watch Portman's entire honest and inspiring speech in the video above.

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