So tired

Is it normal to be so exhausted? I feel like I did in the first trimester - I am ready to lay down on my floor and take a nap! And it is only 11am!!!!!! I go to bed early - about 9:30pm, and don't get up until 6am, and am still ready to fall over anywhere and sleep! Guess I better stock up now - once BBM comes I won't be getting much sleep at all!!!!!