Birth control and clomid

My Gyn just gave me my first round of Clomid and 3 month prior put me on low dosage BC I do have PCOS so the BC helped off set my prolonged I stopped taking them in December to prepare for the Clomid ....but here's the deal my period came on the 28th of 12/2015 and has just been hanging around since so I refilled the BC along with the Clomid and Metformin ..I started the BC and Metformin Monday 1/18 and I'm supposed to start the clomid 1day after the start of my new period which would be 1/28 periods are so long that I can't tell the difference between one or the other sometimes...i plan on stopping the BC one week before I suppose to come I doing the right thing????