In addition to your studies, may I strongly suggest that you keep steadfastly in prayer and in His Word. This has been of great comfort to me. May you not suffer the anxiety of worrying about your grades (I always did too!).
Even though God has the incredible task of upholding all of creation, He knows all about us and our struggles. Jesus said, "What is the price of five sparrows-two copper coins? Yet God does not forget a single one of them. And the very hairs on your head are all numbered. So don't be afraid; you are more valuable to God than a whole flock of sparrows" (Luke 12:6-7, NLT). Our Heavenly Father loves each one of us very much and truly cares about what we are going through.
God has both tremendous power and deep compassion for us, and He is more than able to deliver us from our troubles. He can bring salvation, deliverance, protection, healing, provision, comfort, and guidance when we call upon Him with faith.
May the Heavenly Father reveal to your heart His all-sufficient strength and His loving kindness toward us. Call upon Him with great faith in His goodness, and stand upon His trustworthy promises in the Holy Scriptures. God bless you!