When does my Birth Control become effective?

I started my Birth Control pills on the 21st (A Monday night)

I ended my period on the 18th (The Friday before)

So I started BC 7 days after the start of my period.

When will my BC become effective? How long should my BF and I still be using condoms?

What if I I already released an egg and then started BC? Am I not protected till after my next period?

Is there a chance my BC is not working for me?

I have been taking it at the EXACT same time every night.