Hindi po, hindi yan possible kaya may malaking chance na may error sa lab results mo or may something off sa family records, a few of us actually went through paternity concerns kasi ng blood type mismatch, so hindi ka nag-iisa dito! Type O parent and Type B parent can only give you type B or type O children, so type A is really not possible genetically. I'd suggest mag-retest ka sa trusted lab, maybe in a bigger hospital like Chinese General Hospital or Cardinal Santos, para sure na accurate ang result.