PEOPLE WITH LAST PERIOD JAN4?

we are trying for a baby for 6 months and last period was jan4 and we had based on ovulation calender,my due was feb7 and i had symptoms like mild cramps,nausea,and am damn sure that this time i would surely get luck but when we tested using checkone feb8 noon it came negative but we found later that the product is oly fro after a week of due then we have tested today noon using check one fast which is to be taken on or after due,,,,but it came back negative,but from yesterday am going to bathroom more times but comes very little urine each time.........am very eager to know when to be tested again and by which tester because i live in japan here brand is not much more,,,thanks