Cerelle Bleeding

Lisa
Hi,
My baby girl is 19 weeks old& i startedCerelle around 6/7 weeks ago as I am breastfeeding. Since taking it I've pretty much bled the whole time apart from 2 week break with nothing. I know this is normal I've im searched the internet but I stopped taking it on Weds (last day) it's now Monday evening & im STILL bleeding (very light) but is this normal as I've not taken it in 5 days?!? 
When will this stop? It's been a week straight now of bleeding. Is this classed as my withdrawal bleed? Do you think this could be anything serious?? I worry far too much.
Also before I started the pill I had two very slight bleeds & I mean slight as in a tiny spot of pink on tissue paper.. is this normal too as I thought you're not supposed to bleed whilst BF?
Thanks xx