Hi and welcome to HCM!
Thanks for posting your query here.
In a regular 28-30 day cycle the ovulation happens around 14-16day. 14 days after the ovulation if the ovum is not fertilized it will result in menstruation
. The period from 10 to 18 days is called as fertile period and chances of getting pregnant is more. Is your wife's periods are regular? If they are regular the ovulation can be calculated around 24th of March. As it is 3 days after the ovulation the chances will come down. When you did the pregnancy
test? The timing and the method of testing sometimes will give a false negative result. It can be tested from the first day of the missed period. The accuracy depends on the brand used. An early morning urine sample is the best sample to do the pregnancy test.
The other modes of testing is by estimating beta hcg
levels in the blood. An ultrasonogram will detect a gestational sac
after 20-25 days from the ovulation day.
Please repeat the test again by reading the instructions carefully. If still the doubt persists please consult your gynae.
Hope this is helpful to you.