What should I do about losing the desire to live, abandoning prayer, and neglecting my studies as exams approach?

Chest tightness is often caused by heedlessness of Allah and by sins. Its remedy lies in fleeing to Allah and repenting to Him. Beware of abandoning prayer, read the Quran continuously, increase your seeking of forgiveness and remembrance of Allah, ask Allah for guidance during times when prayers are answered, seek good companionship, and listen frequently to Islamic lectures.