Quitting Smoking and Fatigue: Why after quitting smoking You’ll feel more energetic overall. Quitting can cause depression, anxiety, and irritability. Inflammation is a key component of smoking-related lung diseases, such as chronic obstructive pulmonary disease, or COPD. Smoked 2 packs over 3 days during a weekend. Followers 2. LOL – I felt horrible 6 weeks after I quit smoking. Two weeks to three months after quitting: Your circulation improves, and your lung function increases. Another symptom was swollen lymph nodes around neck which only came and hung around when quitting smoking. A new study shows that quitting smoking after a heart attack has immediate benefits, including less chest pain, better quality of daily life and improved mental health. Why does my chest hurt after quitting smoking? Gave up Smoking Six Weeks Ago Coughing after you quit smoking is normal but difficult to breath is not. This is something that you need to discuss with your personal physician. You might need the assistance of an inhaler for a bit of time and your physician should test from other illnesses that can cause what you are experiencing.