Its common to feel ok during the first day of the accident. The next day or two will begin to uncover your true injuries and should prompt you to seek professional care. The most common symptoms after a car accident is neck pain in the form of whiplash. This can be accompanied by headaches and/or shoulder pain. Without proper care the pain can increase over the course of a month, getting worse day by day.
Often times stiffness, numbness and/or tingling in the legs and feet, will accompany this pain. These are signs of a more serious problem and should be cared for immediately.