What Causes Body Pain?

Hi I'm positive for gallstones, binary colic and gastritis. ..I'm going to have my gallbladder removed And I'm taking prilosec for the gastritis. .I also have pain meds for the stomach cramps.. since the change in diet and meds I've been having random body aches.. cramping in my leg pain under my right armpit and more..can u tell me what's going on? :(