What Causes A Scanty Menstrual Period?

hi i am 28 year old and have a 21 months baby and have a IUD inserted after delivery had a c-section due to high BP now dont have any BP prog. my this month mc period was due on 7th there is bleeding but very less means nothing even comes on pads so iam very concern regarding this. i dont want to be pregnant now. so please tell what would be the problem and what i need to do.