What if i took 3 pregnancy tests and it is all negative, but my menstruation is delayed for 11 days now. the last time we had intercourse is february ?

Pregnancy unlikely: Today's home pregnancy tests are very accurate, but if done too early, a negative result may be due to testing too soon. A correctly done urine test will give a reliable result 3 weeks after sex (when conception might have happened) or 1 week after missing a period. A woman can repeat the test one more time, after 1 week from now, if a normal-appearing menstrual period doesn't happen by then.