What Causes Recurring Fainting Spells After Stopping Intake Of Valparin Chrono?

Dear Sir, Myself Digant Joshi, I am 27 years old. 2years ago I got fainted in company and having stiches on back side of head.At that time doctor says that you have conversion dieases and he advised me to take valparine chrono 500mg (2-0-2) for 2 years. But after 1 year I stopped taking as I am feeling well. Now a days sometimes I again got fainted for 3-4 seconds. So do you please suggest why this is happening again?