Ay mama, ganyan talaga ang adjustment period, a few of us tried switching formulas at first few days talaga sila magseset ng tantrum kasi hindi pa sila sanay sa lasa! I'd say give it around 5-7 days pa before you decide kung talagang ayaw niya talaga, kasi minsan need lang ng time ang babies to get used sa bagong formula, pero kung after a week talaga ayaw pa rin at parang uncomfortable siya or may other signs na hindi okay, maybe consult with your pedia to make sure Nan Sensitive is the right formula for her and check if may underlying issue. Hindi ka naman magpapicky eater dahil lang sa formula switch, yan ay normal lang na part ng paglaki nila, so don't worry too much there!