I'll try to make this short as possible. 

I smoked weed daily and very heavily for 3 months straight, I have been smoking it on and off for 3 years. On and off like few months in between each time I smoke. But this summer I smoked for 3 straight months daily with no breaks at all. I had ADD as a kid, and as an adult I have Depression, PTSD, Stress and anxiety. Thing is, after I quit smoking.. I have been feeling a lot better mentally. I am not depressed, not stressed, and not anxious. I am actually happy. only problem is that my ADD is back, I cannot focus. Nothing makes sense, I can't study, I can't process new information. I feel like my head is empty mentally and physically. How long before my brain goes back to normal? or did I fry my brain for good. I am really freaking out, I already went to my family doctor and explained everything. She said that I have ADD and she wants to give me Adderall. But my ADD went away by the time I was 19. my concern is, is this situation temporary or not? If it is, how long before thing go back to normal?