Urgent!!! 3 days ago, I can feel that chest has a needle-like that's poking me. It hurts a lot. Then today, the pain just went off. Today I went for a jog, while I was jogging, I felt like something is moving up and down inside my chest under my rib-cage. But the pain has gone off. Can someone tell me what is happening to my body? Is it a tumor or my lungs just shrinked?