Women's Health: Menstrual Cycle

I think it depends. If it is different then your usual periods, then perhaps. During your period, you shed the lining that has built up during the luteal phase of your menstrual cycle. It could be that you didn't build up a very thick lining, for various reasons (anemia, thyroid issues, etc). It could be that you are pregnant, and are just having implantation spotting. It could mean your hormones are bit off. Or it could mean nothing at all. If it concerns you a bit, I'd just call and talk to a nurse at your ob/gyn.