Too Exhausted

So I have been working extra hours lately at work trying to help our customer service department get caught up on customer e-mails. I've been coming in at 7:00a.m. and working till 7:00p.m. I didn't think it would wipe me out so much, but I have been soooooo tired! Now I have only been working these 12 hour days for a week now, but I'm not sure I am going to work that many hours for them next week. I didn't realize it would effect me this much! I know it's pathetic. The only thing is that it's extra money, which is why I'm doing it. Money is always a good thing. Being as I'm too tired to write and think any more . . . I'm out! LOL