Withdrawl from THC and Nicotine. Enough?

I was a chain smoker (15+ cigarette/day) from last 5 years. Also, got into daily addiction of weed from last 3 years. Finally, I've taken a step to quit both and I am sure I won't go back to them. I have good will power and I used to be a sportsman. It's been 3 weeks and I've not taken any substance. I am also not taking any replacement therapy. I am on my own and going cold turkey. Also, have been working out for half an hour daily and trying to keep up with hydration levels. Still I feel withdrawl symptoms. I have coughing and blackish phelgm. Also, my sleep cycle has disturbed. I don't feel energetic. My stomach and body aches at times but it's bearable. Anger level is high but manageable. My questions are : How long it might take for physical symptoms to go? Do I need any medication or should see a doctor? Is will power and healthy lifestyle enough?