I am wondering if i am pregnant or if there is a chance of an ectopic pregnancy. i had unprotected sex but took plan b because of my fear precum. i had a period i think 2 weeks later with extreme right sided pain. three neg tests but my period is lat?

Tests are accurate: Home pregnancy tests are very accurate and not affected by foods, herbs, common illnesses, sexually transmitted diseases, vaginal spotting, or medications. A test gives a reliable result by 3 weeks after sex (3 weeks after when conception might have been) or 1 week after missing a period. If done sooner, a negative result may be due to testing too early such as less than 2 weeks after conception.