I missed my period for about 6 weeks since i had sex without protection,4 test strip say negative,my last period was 19th may, pls was i safe?

Yes: It's been quite awhile since you had that intercourse, so if you were to be pregnant, it would have come back positive by now. A pregnancy test is going to turn positive around 10-14 days after intercourse. Use protection if you're not ready to be pregnant. Other reasons for lack of period include hormones, thyroid, weight (thin/heavy). See doctor if persists. Good luck

Maybe...: Hi AdamsM, Assuming you are using the test strips properly, by now, if you were pregnant, your urine test would be positive for BetaHCG, indicating a pregnancy. These urine tests are best done shortly after waking up, since urine can be diluted throughout the day and may give a false positive. If you are still concerned, I would strongly suggest going to see a doctor, who can do a blood test.