My job and being pregnant

Luckily we can have water at our desk but that is it. We aren't able to have snack unless it's candy. And I work 8.5 hr shifts. We are only allowed two 15 minute breaks and a 30 minute lunch. Which makes having to hold my bladder a pain. Also my feet swell from being in a chair all day. And walking around isn't an option and unfortunately I can't prop my feet up either bc it's deemed unprofessional. I'm 31 weeks and to the point I really don't know what to do. I come home with swollen ankles and restless legs. And starving it seems like.