Its been 3m since my last period and i havent had morning sickness etc. i took 2 home urine tests,both turned out -ve. can i be sure im not pregnant? ive also been diagnosed with pcos but my periods have been regaular for as far as i can remember

No: 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 3 weeks after sex (3 weeks after when conception might have happened) 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.