I am off the cigs for about 3 months now. However I feel the worse for it
Constant back pain
Tightness in the chest area
Heartburn when sleeping
Always feeling tired
My concentration has gone to hell.
Is this normal after 3 months
Tiredness is caused by your sleeping patterns being disrupted.
Hunger is caused by nicotine being an appetite suppressant and your body is still adjusting.
Concentration is due to your brain adjusting to the new reality.
This can go on for a while yet.
Backpain and chest tightness you should see your doctor about.