17 dpo and no af????

So, af has always been spot on. I can normally estimate within a couple hours when to expect it. I was supposed to get it yesterday, but nothing and no symptoms, either. I've had some light cramping. Sometimes it's on the left, sometimes the right. I'm trying so hard not to get my hopes up because I've had 3 miscarriages and haven't had luck getting a BFP in almost 2 years (since the last miscarriage). Any advice?