Period is a week late: Still getting negative tests.

When my period didn't show, I really thought that I was pregnant but I've taken three tests with first morning urine and they've all been negative. How could I be testing too soon if I am pregnant? There's two other noticeable changes and that's peeing more frequently and being hungry way more than usual. But many women say they knew or just "felt" they were pregnant and I don't really have any sort of feeling like I am. I'm just lost and actually a little discouraged at this point. Could I get some other opinions?