Hi, I M Facing Depression Problem From Past 6 Years.

Hi, i m facing depression problem from past 6 years. It started after 1 year when i was preparing for iit i used to study beyond my limit and after 1 year i faced depression for the first time and it lasts upto 1 year, i dont understand at that tym so i used reiki treatment but later in btech also i faced depression but minor...later when i started working as a software engineer i faced it again so i consult a doctor and he listened tomy complete story and gave me prodep 20 in morning and sensival 25 for night after 2 weeks i was fine and stopped it later if i feel slightly depressed i used to take prodep and when i started feel ok i discontinue it it happen aroung 1 year now i m preparing for mba from past 6-8 months n now m again feeling depressed and my examz are next month what should i do? Should i take the same medicines.....i felt not studying