Progestin-only pills are often called "POPs" or "the minipill." POPs have less progestin than the combined birth control pill (or "the pill") which contains both an estrogen and a progestin.. POP's are about 95-99.5% effective depending on how close to "perfect" you take them meaning every day at roughly the same time of day with no misses or late pills. They are taken in a continuous cycle, every day with no breaks or interruption between packs and there are no "inert" pills unlike combo pills.
HOW DO POPS WORK?
They make the cervical mucus at the entrance to the womb (the uterus) too thick for the sperm to get through to the egg.
They prevent ovulation (release of the egg from the ovary) in about half the time.
They also affect other hormones, the fallopian tubes and the lining of the uterus.
POPs must be taken at the same time every day, so choose a time and then take the pill at the same time every day. Every time you take a pill late, and especially if you miss a pill, you are more likely to get pregnant.
Start the next pack the day after the last pack is finished. There is no break between packs. Always have your next pack of pills ready.
You may have some menstrual spotting between periods. Do not stop taking your pills if this happens.
If you vomit soon after taking a pill, use a backup method (such as condom and/or spermicide) for 48 hours.
If you want to stop taking POPs, you can do so at any time, but, if you remain sexually active and don't wish to become pregnant, be certain to use another birth control method.
If you are not sure about how to take POPs, ask your doctor or clinic.
It's best to take your first POP on the first day of your menstrual period.
If you decide to take your first POP on another day, use a backup method (such as condom and/or spermicide) every time you have sex during the next 48 hours.
If you have had a miscarriage or an abortion, you can start POPs the next day.
IF YOU ARE LATE OR MISS TAKING YOUR POPS
If you are more than 3 hours late or you miss one or more POPs:
TAKE a missed pill as soon as you remember that you missed it,
THEN go back to taking POPs at your regular time,
BUT be sure to use a backup method (such as condom and/or spermicide) every time you have sex for the next 48 hours.
If you are not sure what to do about the pills you have missed, keep taking POPs and use a backup method until you can talk to your doctor or clinic.
To address your question-no pill is 100% effective so there is always a very small chance of pregnancy. Like it says above the possibility with POP's are about 95% with average use meaning an occasional missed or late pill and they can be as effective as 99.5% when taken perfectly every day at the same time of day with no late or missed pills. You also used a condom which increases the rate of effectiveness. Pulling out before ejaculation is a wasted gesture. It does little to nothing to prevent pregnancy. Men secrete sperm all throughout the sex act, not just during ejaculation. Condom use with oral contraceptives is mainly for STD protection, not contraception-your pill is your contraception. Since you are on a contraceptive AND used a condom then there is so little a chance that it is almost none! No worries! Even if you didnt use a condom and he ejaculated inside of you, there is very little chance of pregnancy. Stop worrying. The stress is what is delaying your period! Contraceptives were made so that women could enjoy their sex lives without worrying about pregnancy. If pregnancy is such a concern that you cannot enjoy your sex life without worry then one has to wonder if you should be having sex? Stop worrying and enjoy yourself!!