Thank you for posting your question here, I will try to answer it to the best of my abilities.
If the condom didnt break then the chances of you getting pregnant are close to nil. Yes, you can start taking the pills right after your next period.
So naturally during that time, it is better to use a condom. I recommend that you dont have sex without a condom till you have at least taken the contraceptive
pill for two days in a row without being late.
I hope this answered your question.