Early Period

For the last 10months I've had an average 39 day cycle....my last period was literally 3 weeks ago, and I've woken up this morning and have started my period approx. 2 weeks early....my husband and I are trying to get pregnant, and I have PCOS which I know can mess things up but this has never happened to me before. 
Is this normal? Does this happen to everyone else as well? Somewhere deep inside my brain I'm wondering if this was a failed pregnancy...? We did have intercourse 2 weeks ago (and have been since) which would be enough time for an egg to fertilise and fail? I've recently started panicking that we aren't getting anywhere and this would give me some hope...