There is nothing greater that you can accomplish on earth than to fulfil God's perfect plan for your life. My prayer is that God will one day use you as an instrument in His Hand to build His church in some part of the world through your life and labours. Your education and profession are only a means of earning a living - so that you don't have to be dependent on others for your earthly needs. But your calling in life is to live for God. So don't make your profession an idol.
God has planned every detail of your earthly life already. That includes your education - the school and college that you were to join, and even the courses that you would take in college. He sovereignly overrules in all of these and ensures that you are finally guided into the right profession. So in some situation, if you didn't get the courses or the openings that you expected or wanted, despite your best efforts, just praise the Lord. Years later you will discover that God was watching over you and sovereignly overruling the details of your life (although you were unaware of it), and that the way it worked out for you was indeed God's best for you ( Rom.8:28 ). Live by faith in this word of God.
God's main purpose for you is that you might be His witness - by manifesting the life of Jesus - here on earth. So don't let your ambitions ever become earthly. Take life seriously. Seek God's perfect will. Live life in such a way that, you won't regret the way you lived, when you finally stand before the Lord in the day of judgment. The GPA that will be important in that final day will not be your`Grade Point Average' (in college), but`God's Praise & Approval' ( 1 Cor.4:5 ). Your score in that will be the only thing that will matter then.
God plans our lives in such a wonderful way. This is what I have found again and again in my own life, which makes me want to give my life more wholeheartedly to His service in the coming days, "to win for the Lamb that was slain the reward of His sufferings". That was the motto of the 18th-century Moravian Christians (now Czechoslovakia), whose leader was Count Zinzendorf.
The perfect plan that God has for your life cannot be hindered by any lack of earthly qualifications. Its fulfilment depends only on your having a humble attitude of mind and faith. So may you always have those virtues.
None of us have managed to live our lives without making foolish mistakes. But I can testify from my own life that God overlooks many foolish things that we have done, when we are humble enough to acknowledge our sin, not blame others, and say in faith, "Lord, in spite of what I have done, I trust in Your mercy that You will fulfil Your plan for my life". Many believers never say those words to the Lord because they are so discouraged by their failures, and don't trust in God's mercy. Thus they dishonour God by exalting their failures over His sovereign power and mercy. You must trust in God and glorify His great mercy. Then it will go really well with you - with each year being better than the previous one.