1 year old refusing most solids and anemic

Hi

My DD will be 1 year old next week. Her recent blood work came back
that she was low on hemoglobin count and so her pediatrician
prescribed iron drops for her. She is a very poor eater and doesn't
eat very much solids and is on expressed breastmilk. I had a few
questions that i was hoping to get some answers for.
1) Can i put the iron drops in the expressed breastmilk or will that
interfere with the absorption. I know that iron is absorbed well with
vit C but if i were to give her 4oz of juice, i am afraid she will
decrease her milk intake
2) Could it be possible that her low apetite is due to her low iron?

She is refusing even milk these days, i think its because of a bit of
thrush she has as well as her front top two teeth are cutting as
well.

Any advice or information would be very much appreciated.

Nitu