Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Discuss whether temporary barrier protection or emergency contraception is appropriate if pregnancy prevention may have been interrupted.
Call emergency services for collapse, seizure, difficulty breathing, inability to wake, severe chest pain, sudden shortness of breath, or signs of stroke.
These are emergency symptoms rather than reasons to wait for a routine appointment.
And for anyone, someone who:
Seek prompt medical advice for repeated vomiting, inability to drink, worsening abdominal pain, faintness, unusual drowsiness, or concerning bleeding.
Heavy bleeding may include soaking through pads rapidly, passing large clots, or feeling weak or faint.
After a minor exposure, a poison specialist may advise routine monitoring without an office visit.
Nausea and breast tenderness should improve as the hormones leave the body.
Spotting or vaginal bleeding may occur several days later.
Contact a healthcare professional for routine follow-up if symptoms do not improve, bleeding continues, or there are questions about restarting the pill.
Follow-up is also important if vomiting may have prevented usual doses from being absorbed or if the current pack no longer contains enough active pills.
And for anyone, someone who:
The article also says
Ask a pharmacist or prescribing clinician how to continue the specific pill.
Instructions vary between combined pills and progestin-only pills, and between brands.
Store birth control pills in their original labeled package, out of sight and reach of children.
A locked location is safest when young children are present.
A daily reminder or pill organizer designed for the medication can help prevent accidental repeat doses, but the original package should remain available for identification.
Every sign above is quoted from the sofidex article on Birth control pill overdose. If you are not sure, err upward — it is always reasonable to be checked.