Please take a second and breathe! I am no longer going to school, but when I did I used to feel overwhelmed like you. Are you going to school full time? Is it possible to cut back on the amount of units that you take this term? If it's possible for you to go half time that would cut down on your stress and anxiety immensely. Perhaps you can speak with your professor regarding the exam you just took, and you can ask them for help on how to study. They love it when students show an interest, trust me. Just focus on one thing at a time ok?