Cramps, no period.

Andi
So the <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">period tracker</a> said I was suppose to start my period about 4 days ago, however I've only had really severe cramps(which I'm used to because I've always had bad cramps- to the point of blacking out) but these cramps are lower & feel like they are right on my vagina bone. Have any of you ever had this problem with these particular kind of cramps? Could this be a sign that I'm pregnant??