Ex pot smoker. Afraid !?

So i used to smoke pot. infact i just decided to quit a couple days ago so i havent even been off the stuff too long. I really didnt like the way things were going. I mean for one i just got home from the doctor and i have bronchitis from last time ! And honestly i feel like im not as sharp as before, like i dont think as quickly and forget easier. I only smoked for about 4 or 5 months and it wasnt alot at all. About once every week or two. Sometimes more. I probably toked somwhere between 10-15 times throughout the course of that time. Also, i smoked tabacco for maybe about a month, around the time when i started smoking pot but quit pretty soon because i felt like that was doing even more damage than the pot in terms of my lungs. My question though, is if i quit now. Will this be permanent. I remember getting an iq test when i was younger (im 14 turning 15 soon) and i scored a 121. I used to get excellent grades and theyre **** this year. So will i be back to my sharper self. And will my lungs recover. I really want to get everything back to normal but i feel like it could be too late.