always sleepy

i had my baby 5 weeks ago and she is an awesome baby she gives me no trouble and she sleeps through the night, through out the day i have alot of help from my mom and my hubby so i dont do alot and neither do i worry about chores, ive been really sleepy lately and im getting about 13 hrs of sleep a day which is making me worry, does that happen to everyone? like i said my baby doesnt give me any trouble so theres no reason for me to be tired