Should Primolut Be Continued Or Stopped?

Hi,

I think I may be pregnant and have been taking primolut for the past 2 days. My period is due tomorrow but I am not seeing or feeling any of the signs associated with my period.

Should I stop taking the meds or should I continue and hope my period comes. If so and the meds do not work and so I am pregnant would the baby be born with defects?

Thanks