Period Help?

So last month I chose to skip my period by not taking the placebo pills in my pack and skip to the next pack. I just finished the last pack on Monday. On Wednesday, I got some pretty bad cramping in the morning and some think blood. Now, about 24 hours later, there is a very small amount of blood. I'm usually very heavy flow so I'm a little concerned. Any ideas if this is just because I skipped my last period or is it something else? Thanks!