Allison Janney accepts the award for best performance by an actress in a supporting role for "I, Tonya" at the Oscars on Sunday, March 4, 2018, at the Dolby Theatre in Los Angeles. (Photo by Chris Pizzello/Invision/AP)

Allison Janney won't be letting her Academy Awards success go to her head as she's heading straight back to work on Monday.

The 58-year-old actress added to a successful few months that has seen her win a Golden Globe, BAFTAs, Critics' Choice award and Screen Actors Guild award for her role in 'I, Tonya' by picking up the Best Supporting Actress Academy Award on Sunday, but she won't be letting success go to her head and was looking forward to returning to the set of her TV show 'Mom'.

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She said: "I have to be at a table read for 'Mom' at 10 a.m. tomorrow morning so I'm going right back to work.

"I'm happy to have a job after something like this because it can go to your head.... I'm going to have a big crash-down after this so I'm happy to have the folks of 'Mom' to lift me up."

And the former 'West Wing' actress admitted she had "given up" on the idea of ever winning an Oscar.

Speaking in the press room backstage at Los Angeles' Dolby Theatre, she said: "I kind of didn't dare to have dreams like this, because I didn't want to be disappointed.

"At a certain point I had given up thinking this could happen to me. I just wasn't being given the right kind of roles in films."

But that changed when her friend, screenwriter Steven Rogers, wrote the part of Tonya Harding's overbearing mother for her, and she is planning to buy him a special gift to show her gratitude.

She said: "He wrote this for me to do just that, to show a different side of me and what I can do. I'll never be able thank him.

"I think I'm going to give him a Rolex. I gotta give him a good present. That's a good start."