I note you seem to be well versed
with the natural method of conception. Going by your calculations & history, you seem to have every chance of being pregnant all things being equal. The dull pain in the lower abdomen could be that of an implantation
. However, i have never been a fan of home pregnancy
tests as it has failed yours truly miserably in the past. Having said that, if your period is regular 28/30 days, & today is already the 24th of September, you will be best suited to play the waiting game for a further week. If the awaited one does arrive, nothing needs be done. If not, go in for a serum B-HcG
test done in a standard laboratory. It will not only provide you with a more accurate picture but also with a titre. The abdominal pain
may well be a mild UTI or even 'pre-period blues' or as i said even implantation. You are better off doing an abdominal ultrasound
if the pain is unbearable & trust (going by your pen-name) as you are a doc, this should be up your street!
Cheers & Good Luck in the baby planning adventure & Wish you Good health!
Dr Praveen Rodrigues MD