You may be pregnant if you have had sexual intercourse and you have symptoms of pregnancy:

• A missed period -- (if your periods are usually regular).
• A short, scant period.
• Breasts that are sore, tender or swollen.
• You feel sick to your stomach, or you are vomiting.
• Fatigue -- feeling more tired than usual.
• You need to urinate more often than usual.
• Mood swings

These symptoms don't usually occur until you have missed your period for about 2 weeks, but this varies from woman to woman, symptoms can occur earlier for some women (sometimes a week after a missed period).