Ehemama kiyanna epa bn..salli prashna thiyenawa...Ge bageta tama foundation....ubala danna kenekgen udawwak ganna ahuwe hariyatama mata saka hara danaganna one nisa
Wihiluwata ganna epa bn me asaranayawa
This thing depends on your wife. if she has regular cycles then no need to worry. but if she has irregular cycles then the chances are high.
Women's periods are depend on hormones that she produces. if there is a hormonal imbalance then dates can change.
normally for a women with the regular cycles, 10th date to 14th date from the start of the periods are the highest fertile dates. since you had sex on the last date of the cycles chances are really low.
don't freak out. there are other things than pregnancy that will delay the periods. stress, hormonal imbalance, eating disorders and if she's on pill that will delay too.
give a week and see. otherwise go see a doctor that's the best. or you can buy pregnancy test kits from pharmacy. something like 100 LKR.
Cool down and don't panic your wife.
Disclaimer : I'm not a doctor and this is my knowledge to my best.