I had unprotected sex 8 weeks from today. I took a plan b 2 hours after the sex. I have taken 6 pregnancy tests since about 2 weeks after the sex and the most recent one was a couple days ago. They all came out negative but I'm supposed to start my period today and it has not come yet. Could those tests be wrong?

It is too early to detect a pregnancy using a HPT.

My suggestion is to wait until you have missed your period by 2 weeks. Then take a HPT using your first morning urine.

Or go to the doctor to get a blood test.

You are probably just stressing yourself out and that is making your period late.

If you are truly worried about becoming pregnant, please use Birth Control and have your partner wear a condom! Or just don't have sex!

“Pregnancy tests are designed to tell if your urine or blood contains a hormone called human chorionic gonadotropin (hCG). This hormone is produced right after a fertilized egg attaches to the wall of a woman's uterus. This usually happens -- but not always -- about six days after fertilization. If you're pregnant, levels of hCG continue to rise rapidly, doubling every two to three days.” When to Take Pregnancy Tests - WebMD: Home Tests, False Negatives, and False Positives (http://www.webmd.com/baby/guide/pregnancy-tests)