Had sex 2 days before starting my antibiotics? Am I at any risk? Help! (on the pill)

Ok. so
I had sex two days before I started antibiotics (I am on the pill) I am not having sex until I am DONE taking them. But am I at risk for being pregnant from having sex even before I started the medicine? Is that possible? I am also on my placebo week of pills and I will end my antibiotics way before my new pack of BC even starts..(still using a backup) So what do you think? I cant get a straight answer on this. I KNOW antibiotics reduce the pills effectiveness and i am NOT having sex right now. I just want to know if it was possible for me to get pregnant because I had sex before starting the antibiotics and now im on my period (placebo week)
Thank you if you can help.

While it is possible for some antibiotics to reduce the effectiveness of certain birth control pills,it depends on the dose,type of antibiotics and birth control pills you are taking. You had sex two days before you started the regime of antibiotics(it would have been nice if you had indicated why) so if you get pregnant ,it would have happened before you began your medicine as opposed to it being the reason why. If you had the protection of your pills before you had sex ,then it is highly unlikely that you will get pregnant because you took antibiotics two days after..I will suggest that to set your mind at ease,you should take a pregnancy test about a month later counting from when you had sex.

If they're making you sick or causing diarrhoea the effectiveness may be reduced, but there's never been any clear evidence that antibiotics themselves reduce the effectiveness of the pill. Talk to your doctor if you need reassurance. Some doctors still believe there's a problem but the research tends to suggest that they're guilty of selective memory.

This is a question for a doctor.