Suffering from chronic nightfall.

I am suffering from chronic nightfall.it occured after every 3 days.initially I got depressed nd felt low with an heavy headache when it occurred.but after the day of occurring I felt rejuvenated.Gradually this disease grew. Nd the time gap for rejuvenation from nightfall increased, I.e.2 days,3 days. This disease also posed as a villainous role in my carrier progress. However I got succeeded thanks to my dedication. But the disease still prevailing vd me even after 9-10 years. Now the problem is that I feel depressed in the day of occurring of nightfall. Then got rejuvenated next day or next day of tomorrow. After one week I again fell depressed even nightfall doesn't occur. I feel low less confidence in speaking and my behavior with a heavy headache throughout the day.I feel that I m less humorous than I was. I laugh less. Plz do some help. Will be very thankful.