The country star is up for eight ACM Awards on Sunday

By Patrick Gomez
April 16, 2015 03:45 PM
Jason Merritt/Getty

Miranda Lambert has a lot to celebrate.

She’s up for eight ACM Awards – and is the only female nominated in the entertainer of the year category (which fans can vote for at!). She will be performing at the ceremony Sunday, and she was personally asked by Reese Witherspoon to write a song for the actress’s new film, Hot Pursuit.

Taking a quick break from her hectic week, Lambert, 31, chats with PEOPLE about her new song “Two of a Crime” (on iTunes April 28) and preparing for her big night:

So Reese just called you up and asked you to write a song for Hot Pursuit?
Reese sent me some notes of some things that were in her brain about it, and then I got together with two of my favorite female songwriters in Nashville and came up with a song. It’s a country song because I’m singing it but it’s also got a Latin feel because of [Sofia Vergara‘s role in the film]. That was something new for me. I’m really proud of it. And we did it so quick – within a month!

Are you and Reese close?
We had texted a few times and I’ve seen her around, but we haven’t gotten to hang out. I think we’d have a blast if we did … maybe even get in a little trouble.

How does it feel to be the only female up for entertainer of the year?
I feel that it’s my responsibility to kind of wave that flag for all the female artists out there, because it takes a lot of work to get a nomination for entertainer of the year and so I’m proud to go and be that person.

Is it hard being nominated against some of your friends?
Jason Aldean is also up [for entertainer of the year], and I started with him 11 years ago doing small tours around the United States. It’s really cool to see that we’ve worked all this time and gotten here. And Garth Brooks was my first concert when I was 10 years old, so it feels really weird to be in a category as a peer now.

Are you excited the ceremony is in your home state of Texas this year?
I’m really excited. I feel like I’m at home. I have a lot of friends and family coming to support me. I think it’ll feel really different than any other previous ACMs just because of the energy in the room. [The AT&T Stadium in Dallas] is a huge place!

Any nerves about performing on the show?
I just try to be prepared. You only get a small time slot, so you have to sing edits of songs that you’re used to singing a certain way every night on tour. A lot of artists sing live to a track, but I play with a live band on stage with me. I partially do that because you never know if I’m gonna mess up at it and they’re ready to follow me wherever I go.

Do you know what you’ll be wearing on the big night?
I don’t. I haven’t even done my fitting yet. I’ll do that on Friday night. I always cut it pretty close, but have a great stylist who knows me and knows my body. I try not to stress out too much about it.

Your husband Blake Shelton is going to be busy hosting the show with Luke Bryan, so are you going solo?
Since he’s been hosting, I’ve been bringing a date. Last year it was my grandmother, and I brought my brother before. This year, I’m bringing Ashley Monroe. She’s nominated with Blake for collaboration of the year and she is my best friend. She’s going to sit with me and be my date.

The 50th Annual ACM Awards will air live from Arlington, Texas, Sunday on CBS.