A while ago I was laying on my left side on the phone and when I sneezed, I felt pain at the center of my chest, but about 2 to 3 inches lower. It was so painful, I could hardly breathe. And when I could finally breathe and move, I lifted my shirt to see if it was red, and I saw a lump under the left side of my rib cage, right where it ends. It feels soft, but when I press on it, it hurts. My stomach hurts right in the center when I cough or sneeze and it feels a little hard. I started feeling some heartburn like feeling, but very little. I also started burping every now and then. What could it be? Could It be a hernia? How can I treat this and make it go away. It's very noticeable and kind of painful, pain at about 1 or 2 every so often.