Thanks for the query.
Sometimes recent illness and usage of medicines can alter the contraceptive
efficacy of the hormonal
So the spotting you are having could be due breakthrough bleeding
To diagnose pregnancy
you have to wait at-least two weeks after the intercourse.
And if you miss your periods this time, go for pregnancy test once.
For more details you can ask me through: http://www.healthcaremagic.com/doctors/dr-sree-gouri-sr/63429