How do you know if you have a pendicitus?

Answer 1

Appendicitis (inflammation of the appendix) usually (but not always) begins with abdominal pain in the center of the abdomen (in the vicinity of the belly button), followed by nausea and vomiting. Later on, the pain migrates to the right lower quadrant of the abdomen.

Appendicitis is a medical emergency. If you are having these symptoms, or indeed any moderately severe to severe abdominal pain, you should seek medical attention immediately.