What Causes Bleeding After Coming Off From Contraceptive Pills?

i was on birth control pills and decided to stop about a week into the pack now i am having what is called "withdrawal bleeding" its pretty heavy and i want to know if its normal. i had my period 10 days ago and im not sure if i should count this as a period. Also, two after stopping the pill i had unprotected sex and i would like to know if i should count this bleeding as aperiod or should i wait for another period before taking a pregnancy test?