I've had a stomachache all day. I thought it was from a lot of food I've eaten, but it hasn't gone away. My right side has started to hurt. If you haven't ran in a while, then you run and feel pain in your side, that's what it feels like. I haven't exercised today though. The pain has gotten a little worse. I feel a little nauseous. It hurts when I move a lot, and when I cough. Should I be concerned?