Possible pregnancy?? Please help?

I had sex for the first time one day before my period should have started. I am on Femodine contraceptive and i drank the morning after 2 hours after it happened and another one the day after it happened.

But the thing is. I've been on antibiotics and toplep and i know both of these medication have an interaction with contraceptives, lowering its effectiveness.

I am now 4 days late. It's the 6th day after I had sex. And yesterday i had some weird spotting but it stopped (was that implantation bleeding?).

Am I pregnant????