No period

Still no sign of my period at all this month. I was supposed to start the 12th and now glow is saying the 18th. I guess we will find out. Hoping I have a baby in there. I've taken a test and it's negative. But apparently it's still early. I'm going to try in a week. And if no period and still negative, I might go to the obgyn! I hate this waiting. Anyone ever been pregnant and gotten negative after negative? I've also been cramping pretty constantly the last two days. And still no show of aunt flow. Hope it's implantation cramps!