Hello,
Since she got her periods after intercourse, she is unlikely to be
pregnant. There are many other factors responsible for missed periods.
Is she taking a lot of stress?
I would suggest that you consult a gynecologist for further evaluation and management. You can also visit my clinic International Fertility Centre located in New Delhi for further evaluation. My clinic offers varied gynecological treatments and services and ensures that you have a successful treatment. You can share your contact details to reach you.