A normal, on-time period makes pregnancy less likely, but bleeding alone does not completely rule it out. People do not have a true menstrual period during pregnancy, yet early-pregnancy spotting or bleeding can sometimes be mistaken for one. NHS guidance explains that pregnancy bleeding can vary from light spotting to heavier bleeding.

If there was sex that could lead to pregnancy, the reliable next step is a home urine pregnancy test:

Seek urgent medical care for heavy bleeding, severe lower-abdominal pain, shoulder-tip pain, fainting, or dizziness, as these can indicate an ectopic pregnancy or another urgent problem.

If she took i-Pill (levonorgestrel emergency contraception) and then had a normal period around the expected time, pregnancy is unlikely.

However, i-Pill can make the next bleeding:

So if the bleeding was unusually light/short, the period is more than 7 days late, or there is any doubt, take a home pregnancy test 3 weeks after the last unprotected sex. Also test if she had unprotected sex again after taking i-Pill, because it protects only the sex that happened before taking it, not later sex.

Get urgent care if she has severe one-sided lower-abdominal pain, fainting/dizziness, shoulder pain, or very heavy bleeding.