You can experience a few dreams on a single night. You can wake up after a dream, then fall asleep again. Then you may see another dream, and wake up again. Sometimes, your body wants you to wake up, to go to the bathroom. Your sleep is interrupted. You fall back to sleep, and may see a new dream, or you may think your first dream was continued. Many people can’t recall all their dreams on one night. They usually remember the last dream before waking up. People who wish to recall dreams, should write them down immediately after waking up, when the impressions are still fresh. After waking up, the first activity is to go to the bathroom and the brain has new input of stimuli as it processes the activities of toileting, washing the face, brushing the teeth and etc. The older impressions of the dream are displaced by the new impressions. Thus the dream is forgotten as the temporary shor term memory is not reinforced by dwelling upon it to make a deeper impression.