Two things: sometimes people wake up at night because they don't have the energy to sleep. sound wierd ? Try eating something with protein in it at bedtime and see . . . .protein because it'll keep your blood sugar at a constant level, versus carbs that will peak and die.
And, on the protein subject, how's your iron count ? I remember, when I was pregnant, that 1/2 way through eaah of 4 pregnancies, my doctor did a blood test to check iron. It was kind of interesting, because at least twice it was right after I was beginning to feel horribly tired, and sure enough -- low iron.
Proteins also help with iron. Because it takes protein to metabolize the iron.
Good luck ! and congrats to you. It's tough to have a job with absolutely NO downtime. But, how will you handle the babysitting AND the new infant during the first 6 weeks ? (You can tell I worked outside the home, right ?)
My hats off to you !!
barb