If your mom is old school low cal, low fat, she may have trouble hearing new information from her DD. Up till now she has been responsible for getting things right for you - and it's been working because you have this doubt -( if your mom doesn't like it, could it be the wrong thing to do?)

could you ask her what her concerns are, and address them one by one as they come up?
If you address her concerns, and she still thinks your approach is wrong, then you can gently say, thank you for your concern mom but we will have to agree to disagree on this one.

Like if she is concerned about fats, just show her something like Mark Sisson's article and tell her this is modern thinking about why it is safe.
http://www.marksdailyapple.com/fats/

Or if her concerns are lack of healthy whole grains, show her the new thinking about whole grains.

She has a LOT to learn and breaking it down might make it more palatable.

I realize this might be unpopular but I would not address her concerns with any Atkins book. Old school people, that just reinforces the red flags from conventional thinking and puts their back up. Something like Mark Sisson's Primal Blueprint with tons of veggies and fruit, or Nora Gedgoudas' Primal Body Primal Mind.

I am 5'3 and if I had figured out the right diet for me at your age, oh my gosh, I would save myself not just from a few extra pounds but lifetime obesity. A few extra pounds are the wake up call! I applaud you!