birth controle

Jacquelyn
I've been on the pill for a little over a year now after my 2nd child.  Before him I was on the IUD.  My question is , is it normal to have missed it even stop periods when on the pill for a long time.  I haven't had a "normal" period since July.  In August I had nothing not even spotting.  This month two days of light spotting some red some brown.  Took tests all two months and negative.   Just need a little feed back.  Thanks everyone.