Leslie Odom Jr. may have been on most 2021 Oscars predictions list, but he still wasn't certain it would come true. "I wasn't made of the stuff that would have set an alarm to be awake for the nominations, but I left my phone on," he tells ET's Kevin Frazier. Sure enough, the call came.

With Monday's 93rd Oscar nominations, Odom Jr. became a first-time nominee twice over: He's up for Best Supporting Actor for his performance as Sam Cooke in One Night in Miami and Original Song for performing and co-writing "Speak Now" from the film.

"I have been watching movies and a lover of the cinema since I was a little boy, so in so many ways, I hope it doesn't sound weird but it feels like the beginning of something," he says. "This feels like I'm not embarrassing myself."

Odom Jr. becomes only the fourth performer to be nominated for acting and songwriting in a single year, following Mary J. Blige, Lady Gaga and Cynthia Erivo. "It means a lot on this movie in particular. This movie meant so much to me and to all of us," he reacts. "I was just happy to be part of it. I was thrilled that I got to bring more of myself to the project. It's deeply meaningful."

While it was only good news for the actor, One Night in Miami ultimately missed out on a Best Picture nomination, while Regina King was snubbed in the Best Director race. For Odom Jr., his own nominations are a credit to King.

"Film is absolutely a director's medium. She cast the vision. She assembled the team. I said it was deeply meaningful -- Regina brought the meaning. So, while her name wasn't read out this morning -- on a list of incredible directors -- I have no doubt that it will be someday, but she is represented any time the film is represented," Odom Jr. says. "It wouldn't happen without her."

As if the Oscar nominations weren't excitement enough, Odom Jr. and wife Nicolette Robinson are expecting their second child -- a baby boy -- any day now. "Look, I gotta go inside and check to see if she hasn't gone into labor right now. Like, we're like that," he reports. "It is any second!"

The 2021 Oscars air live on Sunday, April 25 at 8 p.m. ET/5 p.m. PT on ABC. In the meantime, stay tuned to ETonline.com for complete Oscars coverage.

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