M.P.
J.,
Congratulations on the pregnancy and on the new job. Sounds like it will be very challenging at first - but in the long run a great opportunity.
As far as different snacks go - I always tried to have a few options with me as some days something would taste great, but the next day it would make me sick. I liked fruit, veggies, those little ritz crackers with cheese or peanut butter in them, hot chocolate, yogurt, animal crackers.
Here is a link I found to a list of what not to eat: http://www.babyzone.com/pregnancy/is_it_safe/article/food.... Otherwise, you can just google it.
Depending on your relationship with your employer, I would probably wait for at least another couple of weeks if you can.
I remember with my second pregnancy - really feeling GREAT durning my second trimester. But the first and third were very exhausting. It is probably a combination of your schedule and the pregnancy, but it is temporary. Hang in there and try to sleep as much as you can. A little 20 - 30 minute cat nap while your 2 year old watches Dora with you on the couch might be just what you need to help keep your energy up.
Good Luck!