Making it through the workday tips

Please help!

I'll be 33 weeks on Thursday (November 3) and I don't go on maternity leave until December 14 (a week before my due date). I did this so I'd be able to spend as much time with my rainbow before I go back to work. I didn't want to go too early. The extreme fatigue I had from my first trimester has come back with a vengeance. I've never been this tired. I go to bed at 830 every night and my husband has to pull me out of bed at 7 every morning so I can be at work for 8. I used to wake up at 530 every morning without an alarm clock. I work full time as a preschool teacher, and we're shorthanded as it is so I know I can't cut my hours, and I know I wouldn't be able to ask my boss to let me nap during the day. I also don't like coffee. Does anyone have any tips to help me make it through the workday? I don't know how I'm going to make it to the end of my pregnancy if this is how tired I am at 33 weeks! Thanks in advance =D