Normal to keep getting darker?

Emily

I found out from Doctor I was pregnant on Friday. Had some pinkish-light spotting twelve hours apart on Thursday, nothing on Friday, then it was the same as Thursday yesterday but with a couple small dark blood spots like the one in the middle here, then I just had this which is the darkest he whole time. Should I start to be worried? Does having PCOS and first time pregnancy have anything to do with it?