The good thing is her comments made you THINK about your photography. That is important. Some times tis is necessary lest we stagnate. Next time she comments thank her for her opinion, explain you have given it a lot of thought, and you feel you are doing just fine. Which you are. Now if mom was say Imogen Cunningham or Dorthea Lang I might give her words a bit more thought.
My dad does this on occasion. What burns my hide is he is often right when he makes the comments.