Katherine Heigl on 'Grey's Anatomy' Emmys scandal: 'I shouldn't have said anything'

Katherine Heigl is still answering up to that "Grey's Anatomy" drama.

The 37-year-old actress, who played Dr. Izzie Stevens on the medical drama before departing in 2010, ruffled feathers when she reportedly pulled her name from Emmy contention. She clarified during an appearance on SiriusXM's "The Howard Stern Show" on Tuesday that she didn't pull her name -- she just never submitted it in the first place.

"I didn't feel good about my performance," she explained, clarifying it wasn't an issue with the writing. "There was a part of me that thought, because I had won the year before, that I needed juicy, dramatic, emotional material. And I just didn't have that that season."

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As for why she feels she didn't get that "juicy, dramatic, emotional" material -- after winning the Emmy for Best Supporting Actress in 2007 -- Heigl says she hopes it wasn't because anyone behind the scenes was against her.

"I was treating it a little black and white and taking it a little personally, but I think there were 12 series regulars on that show, and everybody deserved their juicy, dramatic, emotional season," she reasoned. "I'm not a writer, but I imagine it must be difficult to do that for everybody."

Looking back, Heigl admitted that she could have avoided the drama by not saying anything.

"I was really embarrassed. So, I went in to Shonda [Rhimes] and said, 'I'm so sorry. That was not cool. I should not have said that.' And I shouldn't have said anything publicly," she recalled. "But at the time, I didn't think anybody would notice...I just quietly didn't submit. Then it became a story, and then I felt obligated to make my statement. And...shut up, Katie. I should have been like, 'It's personal, whatever.'"

Years later, Rhimes called Heigl out while discussing her "no a--holes policy" on "Scandal," saying, "There are no Heigls in this situation. I don't put up with bulls--t or nasty people. I don't have time for it."

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Heigl also opened up about drama surrounding another one of her projects, "Knocked Up," which landed her in hot water with Judd Apatow and Seth Rogen after she seemingly blasted the movie as "sexist."

"I liked the movie a lot, I just didn't like me," she explained. "She was so judgmental and kind of uptight and controlling and all these things. And I really went with it while we were doing it. And a lot of it, Judd allows everyone to be very free and improvise and afterwards, I was like, 'Why is that where I went with this? What an asshole she is!'"

As for whether she bashed the film or not, Heigl claimed it's a matter of a Vanity Fair quote being taken out of context, after the reporter brought up the fact that women felt the movie may have been a little sexist.

"I felt obligated to answer that. So, I tried in my very ungracious way to explain why I felt that it maybe was a little," Heigl said. "If you read the whole quote, I'm just saying, 'That can be the nature of broad comedy, they're exaggerating stereotypes, that's what makes it funny.' But they just took the sexist thing out."

The rom-com star gushed that she would "love" to work with Rogen again, but doesn't think the feeling is mutual -- "I think he's really mad at me," she said. Still, she admitted she wants to make things right.

"I probably should have [called], but I did it publicly instead," she said of apologizing at the time. "I've thought about like, writing a note, but I feel embarrassed. I don't want it to feel insincere on any level."

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Having developed a reputation for being difficult -- which Heigl has often refuted, reasoning that just because she has an opinion doesn't make her a "B-word" -- the actress told Stern she sought therapy.

"I was feeling completely like the biggest piece of s--t on the bottom of your shoe," she revealed. "I was really struggling with it and how to not take it all really personally and not to feel like there's something really deeply wrong with me."

"It was just a decision that was made, like 'This is a juicy story, we're going to go with this whether it's true or not,'" Heigl added of rumors that she is rude. "I remember doing this little independent movie and being afraid to say anything about anything. I remember wearing shoes a size too small because I was afraid to tell wardrobe that they weren't big enough, because I didn't want to be difficult."

Meanwhile, Rhimes has admitted to killing off a character on one of her hit shows because she didn't like the actor -- but she didn’t name names!