I'm experiencing pain below my belly button, in the center of my lower abdomen. its only been a week since sex, but could i be pregnant?

Lower abdominal pain: The site and and time of the pain started makes me to think you may have bladder infection. Pregnancy always possible, simple home tests available to clear your doubts.

Unlikely: Always important to check a pregnancy test if you had unprotected intercourse. Doubt that one week would be long enough for you to have abdominal pain symptoms from an early pregnancy.

Need more info: This kind of complaint is more commonly caused by urinary infection or even a colon problem. Please make an appt with your family physician to find the cause.

Unprotected sex yes: If the sex was unprotected, then yes you can become pregnant.