from what i know of birth control pills, it normally takes a few months for your body and its ovulation cycle to return to normal. you may have ovulated at around the normal time that ovulation should occur for you when you’re not on the pill, but chances are that since your body is still trying to adjust to not having to take the pills ovulation may not even have occurred that month. the best thing to do in any case if you’re uncertain is to just wait until about a week after your missed period and take a pregnancy test. this will give you some insight as to whether or not you may be pregnant. good luck 🙂 and let me know how things go.