Suggest Remedy For Lack Of Sleep In 3 Year Old Child

my 3 year old son for the past 4 days has slept more or less all day then still sleeping 12 hours at night , he seems to have no energy is very pale i have just moved to new area so need to book with a doctor do u think i should take him to a emergancy doctors as he is a small child for his age and has been under peads for concern about his weight gain and height