Actually, in MA, they do allow for same-day single station retests, if the failure is recognized by the chief examiner before candidates leave for the day, which should have happened. It is also possible that the failure wasn't recognized immediately, or was the result of the failure of the examiner. Consider contacting the exam organizer, as again, this should have been caught same day. OR, make sure that you didn't fail more than one station.
Otherwise, study the station sheets (either from your program, or the state exam sheets), consider simple scenarios that could be covered on the exam, and review the critical criteria and mainstays of the assessment. Rarely do students fail for number of points lost, but more often for critical criteria. Make sure you are assessing (AND TREATING) your patient's Airway, Breathing and Circulation, ensuring you listen to the answers to your assessment questions and responding accordingly. When administering a medication, think, and verbalize indications, contraindications, dose, route, medical control, etc.
Good Luck!