That's because your body is overwhelmed. You can avoid this from you know, eating everyday. Even it's a little HEALTHY snack, like an apple or something. Eating a snack isn't going to excuse all the nutrients that your body needs, if you have a healthy diet you'll be just fine. I wouldn't recommend going days without food though, especially water.<span />
Don’t freak out too much I’m sure as long as your still able to walk and it doesn’t hurt when you want then you should be fine but if the pain continues you should go see a doctor