I'm on contraceptive pill.but i still got pimple a week before my period comes.pills should stop it from popping out right?

Unclear question? : I'm not sure what your question is? Your birth control pills won't have any particular effect on THIS premenstral pimple that you are experiencing. Be sure to not pop it yourself, and let it self resolve. Check with your prescribing doc about your pills in relation to acne. Sometimes women experience an overall improvement in their skin, but not always! Hope this helps!