The following are the most common signs of internal bleeding: vomiting, severe nausea, very low blood pressure, severe weakness, fainting, acute vision problems, dizziness due to blood loss, severe headaches, deep purple skin in areas due to blood pooling internally, abdominal pain or bruising around the navel, numbness in any area, weakness on one side of the body, pain with no visible injury, abdominal swelling, shortness of breath, chest pain, diarrhea, areas of swelling for no apparent reason, bloody or dark vomit or stool.