Exhausted!!

Now I know I have a lot on my plate, pregnant, work full time plus I'm a full time nursing student. I had my first clinical day yesterday, about 10 hours long. Got home couldn't keep my eyes open. Was in bed by 7:45 and slept for over 12 hours. But I am still so tired!! I really hope this exhaustion goes away in the second trimester. Anyone else feel like they just can't stay awake?