Ah, yes, it can be very difficult to get used to hearing aids, and they do feel too expensive, especially if all you need them is for talking to your kids.
So basically, once you locate the hearing test results, or get your Mom to retake it, there's going to be a number for each frequency tested. If any of the numbers are smaller than 45, you just use that number as it is. For any frequency where the number is bigger than 45, enter 45. Got that?
Also, make sure hearing protection is turned on. That should help with discomfort from sounds being too loud.
And finally, what I found most helpful is to fine tune the hearing aid sound. It's in Settings->AirPods (shows up when AirPods are connected to phone)->Hearing Assistance->Adjustments.
Sit your Mom in front of a TV, turn on a news show, or other program where people are talking in a steady, even tone. Then slide the Tone and Ambient Noise Reduction sliders left and right until she finds a level she's comfortable with.
It won't get your Mom's hearing back to the level where you never have to repeat yourself, but it might cut back on the number.
Oh, another tip is that talking louder doesn't necessarily help with comprehension. In most cases of hearing loss, the main problem is you lose the ability to distinguish between consonants. So talking at normal volume, but taking care to clearly enunciate consonants helps. Rewording what you said, so that you switch to words that are easier to hear can help, too. You and your Mom should try to identify exactly which words she couldn't figure out instead of repeating the entire sentence over.
Good luck, let me know if it works out.