pupu ni baby

mamsh..ask ko lng normal ba n ngbbgo color ng pupu ng baby pg ngpplit ng milk fomula.. from enfamil a+ 0 to 6 ..to lactum 0 to 6.... ung pupu nya nging dark color.. pero as of my observation wala nmn ngbgo sknya msigla p den malakas dumede d nmn xa ngrarash at ng pupu nmn xa everyday..same kc ng takal ung 2 ..help po..baby is going 4 mos. nxt week