Hi. We all need phd's to be women and figure out our cycle, don't we? It can be so complicated. My guess is that this is spotting due to either a hormonal fluctuation which wouldn't be uncommon if you are taking metformin (it is fairly common). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3125003/. And some women do spot slightly when they ovulate. Was the sex unprotected? There is also that implantation bleeding. But I will tell you that no one I know actually has ever had that happen. It's something that I guess does to some people but don't think it is all that common. I have had spotting when my hormones are wacky. Is it just the spots or does it fill a pad/tampon or anything like that?