working while pregnant.

So I'm in the military and still work the regular shift. Pt in the morning then 9:30-5 after. Which is fine for me. This month they decided to start putting me on a 24hr shift 9:30am to 9:30am every 5 days and it's messing up my sleeping. I can never get on a good sleep schedule when I have to wake up at 5 for my regular shift. Do I have a right to be mad or am I being a cry baby?