I have gone through your query and understood the concern. If you always have regular 28-30 day cycles, the period when you had the sexual encounter was your fertile period and hence the chances of conception are high. Therefore, in the current scenario, the ideal thing to do is to get a proper clinical appraisal, a trans-vaginal sonogram to know the status of the pelvic organs and also get a confirmation/exclusion of pregnancy
through the blood test
. Since you have not responded to several attempts at inducing a period, do not go for any further self-medication
, but take the advise of an expert. Hope this helps.