Ay, normal yan! Nangyari na rin sa akin dati when I first started freezing milk, medyo off ang smell pero okay pa rin sya. Basta hindi sya sour-sour talaga or may weird taste, pwede pa ring i-give sa baby. A few of us mums noticed na sometimes ang frozen milk gets that slight soapy or metallic smell kasi ng lipase enzyme, pero it's safe, hindi rin lahat ng babies affected. If you're worried though, better check with your pedia para lang sure, lalo na first time mo pa lang, para ma-ease your mind!