What is happening to my body?

I went off the pill a little over a month ago. I am not having a normal time of the month at all. I have pcos and usually have extremely heavy periods, but not this time. I was supposed to start my period three days ago and all I've had is minimal spotting of brown and almost a little pink in a wipe. I've never seen such little during my "cycle". What is happening to me? Am I just having a slow period or is this implantation bleeding? Im emotional and so tired! Is this even worth taking a pregnancy test?