Mommies I have a serious Question.

For 2 days now I've been Noticing my almost 4 Month daughter who has been breastfed ever since she was a Newborn. I kept her strictly on the Breast for a Month. No bottles or Pacifier of any Kind.

When she got about 2 or 3 months I started pumping and giving her Bottle and I have been using Formula introducing it to her. She's been taking a Bottle just fine all of this time and no I have a time with her Taking her Bottle, she will not have it sometimes and when I pick her up she does Q's and sucks and smells toward my Breast, I know she is Hungry but why is she starting this all of a Sudden