A certain level of anxiety is normal prior any major events, in your case board examinations. But if the anxiety symptoms are overt and hampering your attention concentration and associated with feeling low most of the day, reduced interest in routine, fatigue, lethargy, worries etc, likely possibility of depression.
Next Steps
Get yourself to consult a psychiatrist.
Health Tips
Given your age on onset, family history of any psychiatric illness, menstrual history and substance use if any and routine blood investigations should be considered once.