Hi, I am 37 years old. Preparing for pregnancy. This month my period had not came yet. It was 23 april last month. It S for the first time. Only. Once it occurred when I was in medication Otherwise never. Always 28-31 days period never late. Early but never late. I did urine test on6th day. But was negative. Some of friend suggest to test after 15 days of missed period for best result. Due to late ovulation. What should I do. I had sex after 20 days of last cycle. Thrice should I be positive?