You might want to bring this up with one or two of your professors - show them the curriculums and the times you have tests scheduled, and see if you can work something out with them so that the times don't run into one another.
It's entirely possible that the professors don't expect students to take these courses all in a row, so you might just be unlucky - but it's also possible that students aren't supposed to be taking all these courses at once (perhaps a mistake in setting up your curriculum), and a professor could spot that right away.
At the very worst, you'll find inflexible professors who refuse to help you - and it'll be no worse off than if you hadn't tried.