Given your situation, weighing the benefits of the I.B. program against the challenges you're facing with the second language course is important. Here are some thoughts to consider:

1. Long-term Benefits: The I.B. program offers significant advantages regarding university acceptance and job opportunities. Consider how much these benefits align with your future goals and aspirations.

2. Current Well-being: Your mental and physical health are crucial. If the stress from this course affects your sleep, self-esteem, and overall well-being, it's important to address these issues. Chronic stress can have long-term negative effects.

3. Support Systems: Look for additional support, such as tutoring or study groups, to help with the second language. Sometimes, external help can make a big difference.

4. Teacher Communication: If possible, try to communicate with your teacher about your struggles. They might offer additional resources or adjustments to help you succeed.

5. Alternative Solutions: Since you can't change courses this year, focus on strategies to manage stress and improve your performance in the current class. Mindfulness, time management, and seeking help from peers or counselors can be beneficial.

6. Future Decisions: If the situation doesn't improve, consider discussing your options with a school counselor or advisor. They can provide guidance on whether continuing in the I.B. program is the best choice for you.

Ultimately, your health and happiness are paramount. If the program's benefits don't outweigh the personal costs, it might be worth exploring other educational paths that align better with your well-being and goals.