You should check for a hernia by lying down and placing your hand on your belly. If it feels hard, there is a chance that you have one. You can also check yourself for a hernia during certain activities such as lifting heavy objects or straining when you sneeze. Pay attention to the difference between normal abdominal pressure (felt when laying on your back) and the feeling of something in your abdomen pressing against the wall of your abdomen (a symptom of an abdominal hernia).