Hello, I Have Had Bad Pain In My Left Side

Hello, i have had bad pain in my left side under rib cage that travels to my back. I had the pain for several days and kept massaging my back and front side. I assumed it was gastritis for I finally took some baking soda and it seemed to help alot. Now i developed small itching bumps on my center left back side and on my front left side. My whole left front side under breast is tender to hot water. Can i have shingles or is this just a side effect from too much rubbing and the gastritis?