What Causes Lack Of Menstruation After Discontinuing Birth Control Pills?

hi im on a birth control pills and not sexually active,my doctor told me that i should take a pill a month before my husband getting home,his working abroad,and his coming back this april,so i take a pill March 3 2015,on my first day ,,i finished the pack ,and im on the second day without taking any,,and i dont vevn have my period,,what should i do?