I would just like to know if I should be worried I just turned 35 years old and my husband had a vasectomy 4 years ago we have five children so we are not looking to have anymore. I am 16 days late for my period and I am very regular never been late except for when I was pregnant. I have been experienceing cramping, headaches normal things for right before I start but period still hasn't come. The last couple days I have been dizzy and have no appetite. I have taken a hpt and they have been negative. Should I be concerned?