Sounds like you could be to me! Take another test still negative get a blood test done. Good luck! :)
I was in your boat not to long ago myself. I took 2 HPT's before my af was due (both negative) and one the day my af was due (negative) Well, my af never came-took a test 8 days later and BFP.
7 weeks, 6 days pg
It sounds like a blood test may be the best idea for you.
I agree with Lisa, the first tests were probably too early to detect pregnancy. Since you're a few days late now a test early in the morning should detect if your pg or not.
I would take another test, try to do it first thing in the morning or wait at least 4 hours after you go to the bathroom. You might have taken the other tests too early. A blood test can detect the smallest amount of the hormone so it should come up with a blood test. Good luck