Just above belly button on the right side if i press firmly, the pain is extreme, what's wrong?

Many possibilities: Without more information, it would be impossible to say. How did you discover this? Were you experiencing any symptoms that made you push deep on your belly? It is normally uncomfortable to press firmly in this area, so there may be nothing wrong. Medically, we would want to examine and make certain it is not something urgent (like appendicitis). Lots of possible explanations.....

Clinic visit needed: There are many causes of abdominal pain, some of which can be simply annoying, like constipation, others can be deadly. The best way to make sure it's nothing dangerous is to be examined by a health care provider. Most of the time the cause can be determined with a physical exam and a few simple tests. Less often, an imaging study or looking inside the gut with a scope (endoscopy) is needed.