Hey,
You should be paid what you deserve and have proper rest times. Even if you're scared, you need to bring it up with your boss otherwise this will become the norm.
crummyOtter0
Something that goes a long way for me is to take 5 mins between tasks to just walk around breathe deeply. There's a point after which you develop fatigue, so if you can take a breather just before that, an extension of work hours could be much easier for you to tackle.