School is challenging but God is bigger than all our problems. Lean on Him and he will grant you your success. Continue to work hard and keep trusting in Him to see you through. Remember "You can do all things through Christ who strengths you." Philippians 4:13
Don't be discouraged if you are not granted with what you wanted, It just wasn't for you. Just keep holding on to your faith and trusting that God is almighty. The desires of your heart that will take you to new heights with Christ will be granted. God knows what is best for you! You don't. So don't let one minor set back become a major set back.
The blood of Jesus is able to cleanse your sin. He died in your place - the just for the unjust; the righteous for the unrighteous; the sinless for the sinful. Isaiah described this process "Surely he hath borne our griefs, and carried our sorrows, yet we did esteem him stricken, smitten of God, and afflicted. But he was wounded for our transgressions, he was bruised for our iniquities. The chastisement of our peace was upon him; and with his stripes we are healed" (Isaiah 53: 4-5)