Due to low supply of breast milk, I have been feeding Nan pro stage 1 twice daily to my 2 month old baby. Since few days, I have observed baby getting fussy and cries while breast feeding when milk flow is slow. This happens usually in the evening and night. In the morning she is fine and takes in breast milk. When feeding from bottle she sucks happily when flow is high but when i control the milk flow in bottle, she cries nd gets irritated when the flow is low. What does this indicate?