overworked.

I am 6w3d,and I work a pretty demanding job. Mixing and making dough, tending to customers, hand mixing sauce, and so on. My legs have started to swell and I have cramps when I'm on my feet for too long. Well my boss just doesn't want to compromise. I told her that I'm being overworked, and if she doesn't want me to end up on bedrest, or worse, quit, she needs to cut my hours and schedule me when I have more help. I got my new schedule and I'm on there for almost 40 hrs! I'm so conflicted on what to do. I don't want to leave my team high and dry, but at some point I have to say enough is enough right? What would you do?