spotting..confused!

Amanda

So according to OPKs I ovulated around July 10-11th so today I'm about 14 DPO. I got a blood test to confirm I ovulated. My period is due today...however I've only had spotting for the past 3-4 days and no cramping like I normally do. I tested today and it was negative. So I'm either about to start my period or something weird is happening?? Has anyone had spotting right when their period is due and still ended up being pregnant?