Natalie Portman Recalls 'Heartbreak' and 'Difficult Times' at Harvard

College didn't come easy for this Oscar winner.

didn't come easy for Oscar winner Natalie Portman.

The 33-year-old actress was the keynote speaker at Harvard College's Class Day ceremony on Wednesday in Cambridge, Mass., and admitted to the graduates that she struggled during her freshman year at the ivy league university. 

"When I came in as a freshman in 1999, I felt like there had been some mistake," Portman said, adding that she was eager to prove that she "wasn't just a dumb actress."

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"When I got to Harvard just after the release of Star Wars: Episode 1, I feared people would assume I had gotten in just for being famous, and not worthy of the intellectual rigor here," she recalled. "It's easy to romanticize my time here, but I had some difficult times here."

The Black Swan star disclosed that at age 19, she was dealing with her "first heartbreak," and was "taking birth control that's now off the market due to its depressive side effects."

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Portman graduated from Harvard in 2003 with a degree in psychology and said that is was then that she realized her true calling.

"I admitted to myself I couldn't wait to go back and make more films," she said. "I had reclaimed my reason."

Portman isn't the only brainy celebrity. Check out these stars who've earned advanced degrees: