If you're way behind in your reading and overloaded with work, talk to your professor or teaching assistant about it and see if there's a more efficient way to get through the reading. You can explain that you want to do well and that you have a lot on your plate, and you can see if they can help you, because sometimes they'll tell you what sections are most important, or what reading you don't have to do, or at least what information you should take from the readings so that you can be most efficient and effective with your time.