What Causes Pain Radiating From Shoulder To Leg With History Of Appendectomy?

A healthy 34 year old female with right side (leg up to shoulder) pain. No relief in varied positions (sitting, laying down, standing or moving about). Not pregnant - weight about 105 and 5 2 . Pain began about 15 hours ago. Birth control pills only medication taken. Aspirin has not relieved pain. Appendectomy only surgery (6 years ago)