20 days?

So my husband and I are ttc, therefore we track my period through this app. My period is always right around 28-29 days apart. This time, however, it is only 19-20 days since my last period. Also, my blood was like an orangish color, which I've read in places that it could've been either a) miscarriage, b) infection of some sort, or some other cause. I was just curious if anyone else has had theirs like this or suggestions on what could have caused it.