Implantation or period?

My fiancé and I are trying to get pregnant. After trying for a baby Dec 26th while I was ovulating, I felt sick& the whole nine yards. But I'm having light bleeding Jan 6th a week before my period is due(Jan 12th). I also have bad cramps. What does this mean? This would be my first baby. I've had a missed carriage in the past and it wasn't anywhere near this light. I'm honestly freaking out.

Thanks so much for your replies, it's grately appreciated!