What Causes Delayed Periods And Pregnancy Test To Be Negative?

I was supposed to start my period on 23-24 of October, it is now the 2nd of November and still nothing. I've been having some slight cramping, and some occasional breast pain..nothing unbearable but definitely noticable. I also feel like I've been more tired and have been bloated for the last week and a half. My period is very regular...never missed one. I've taken 2 home pregnancy tests and they've both come back negative, is there still a chance that I could actually be pregnant and just test too soon. I just want to know if I should go to a doctor for a test or what i should do now.

Kendra, 23, Nebraska, 5'4, 145 pounds