Had unprotected sex and got period the next day but this one is late. took pregnancy tests and both neg. should i still be worried about pregnancy?

Always worry...: Always worry if not wanting a baby but still having sex without contraception. However, today's home pregnancy tests are very accurate and not affected by foods, herbs, common illnesses, sexually transmitted diseases, or medications. A correctly done urine test gives a reliable result 3 weeks after sex (or when conception might have happened) or 1 week after missing a period.