Implantation Bleeding or Something else?

Rachel
Hey, 
So we've been trying for a baby for little over a year. After paying for private fertility advice, my periods finally fell back into a regular cycle.. 28 days exactly, almost to the hour. 
This month, I had really light bleeding the 2 days prior to my AF rearing her ugly head. This stopped however and my period didn't turn up. 3 days on, I had very light brown bleeding with some lower tummy cramps/pressure.. 
What would you suggest?