AIO my gf starts playing on her phone in the middle of an argument

I want to confirm if this is normal or not. I had gotten into a minor argument with my GF the night before about not eating in the bedroom and the next morning I was trying to explain why I did it and why some leeway was needed.

In the middle of me talking so just pulls out her phone, and then doesn’t respond to me anymore. Then when i stop talking she just keeps texting other people for the next few minutes.

AIO when I walked out there angry about the disrespect as I am trying to resolve an argument but she was just messaging other people.