Why am I soo tired?! help..?

Hey everyone. Okay, so im almost 21 weeks pregnant. This is my 2nd pregnancy, and I remember with my first son, I wasnt THAT tired. Expecially at this stage. I do have an ear infection, and I am taking safe antibiotics. Anyways, I sleep almost all day! My hubby lets me and watches our son. Luckily he's there for me. But Im not sure whats wrong with me. Is it normal for me to be sleeping so much? I will sleep for like 8 hours during the nite, eat breakfast, then fall back asleep for another 4 hours, and now I feel like sleeping AGAIN! I do have diabetes, but my sugars are wonderful. SO, if anyone can just talk to me and tell me if you were/are liek this. THANKS! And God Bless!