The appendix is located not in the left abdomen, but, in the lower right abdomen.
When the appendix is inflamed, first symptom is a central abdominal pain than in a period of 2 days moves to the lower right abdomen as a localized pain.
If the appendix burst, a generalized pain, most intensive one, with abdominal swelling are present.
Appendicitis pain, indeed, becomes worse with walking, coughing and other movements, and hand pressure makes it less intensive, but, reappears after the hand is removed.
I guess you made mistake writing left, but meaning right side.
(right side abdominal pain could be due to inflammatory bowel disease or diverticulitis)

Visit your physician!