Please help, I think I'm pregnant but my pregnancy hormone level is 7 and I am one week overdue

I am regular as clockwork but this time my period is one week late. I have taken 2 home tests both of which were negative. I've been to the docs and he took a blood test which also proved to be negative as my hormone level was only 7. I have had low abdominal cramping pains at the tops of my legs, a hunger like you can't imagine, dizzy spells, everything I eat tastes wrong and I am tired and thirsty all the time.