Hi Anlib,
I'm in my 20's as well and all i can tell you is everyone who gets low grades in school passes through this phase.
Remember that life is a game and don't take anything seriously.we don't control anything in life so chill out and try to learn from everything that you encounter in life.
Listen to your heart whether its says to work or retake the course.(if a thought disturbs you for more than a week that is coming from your heart so give it sometime and see what it says)
Don't feel that you are stuck in life. Its also a situation you are put in to better yourself so learn from it as well because nothing is permanent and this to shall pass.
There are many 10-day Vipassana meditation course retreats in sweden.It is the oldest meditation technique in the world which was taught by gautama the Buddha
