What Causes Dizziness Attacks,weakness,loss Of Memory And Vomiting Sensation?

hello, I am 23 years old male, i was accidentally shot in the head with a bird bullet rifle when i was 9, it got me into a coma for 20 days and i was operated on so that the bullet was removed from my head. I have been taking epanutin for 13 years now, and 5 years ago i took kepra because i was feeling slight headaches, however i stopped it because it caused very high depression and stiffness in movement(i have weakness in my right arm and leg). So i dumped the kepra, i am not using it anymore. 2 months ago, i have been experiencing dizziness attacks that will last for a minute or two but the after effects would last for several hours and sometimes for several days, these effects are weakness in body, vision, feeling like i want to vomit, i lose memory and feel frightened. I want to know what is causing these attacks and if its from the medication or not. thanks