Taking an i-pill can throw off your cycle for a month or two, even after one normal period in between. The hormone dose is high enough that your next one or two cycles can still come early, late, or with a different flow.
Next Steps
If your October period doesn't start within a week of when it's due, take a home
pregnancy test to rule that out first. If it stays delayed and the test is negative, your cycle is likely just settling after the hormone dose.
Health Tips
See a gynaecologist if you miss two periods in a row, or if you have unusual pain or heavy bleeding.