Bah, can’t access that quiz at work.
Yup, you’ve got just enough that people assume you’re not native to Iowa but not enough to make a regional identification. I was surprised at how strong an accent your mom and sister have compared to you, actually.
Mom always has, never really lost hers. I notice it a lot more in my cousins. If I was down in TX for a couple years I would expect it to get stronger. It still sounds ‘right’ to me since that is how mom talked. It always feels like going home when I go back to TX. Even though I ahve not actually lived there very long.