Will a 10-day delay in my period mean I might be pregnant?

Patient's question:

Detailed medical condition and consultation purpose: Want to find out the cause
Duration and persistence of this episode: This month
Current general condition: No discomfort, feeling good
Medical history: None
Ancillary tests: None
Other: Contraception measures are withdrawal (coitus interruptus)

Doctor's answer:

You can use a test strip to check.