What are you worried? Do you think it might be pregnancy or are you worried about something else? Because it could be millions of things!!!
Funny story- do you know where the meaning of the term hypochondriac came from? In anatomy, your hypochondriac region is (under the ribs) your abdomen. Pain in this area is extremely hard to diagnose, because it could be so many different things and pain in the abdomen is a really vague symptom. So when people would come in saying they had abdominal pain and the docs had no answers for what it was about, they would just label the person with hypochondriac pain and later it just turned into them being dismissed and labeled a hypochondriac.
Oh, luckily now we have much better technology and knowledge about medicine. I would ask a doc if it persists or you experience other symptoms. It could be something as simple as gas, bloating, or a stomach bug, or it could be something worse. It's always worth getting it checked out.