Advice. Please, if you criticize, do not comment.

Hello, so. This is my first pregnancy. I never thought it would happen. So, basically, when I first got pregnant I hadn't had a cigarette the first 2 months. I had already quit. Well, one stressful thing.lead to another and I started back. Mind, not a lot. Here and there. I've been trying to stop since. I don't even smoke a whole cigarette. I am currently 20 weeks. I've had 3 cigarettes in 3 days, again, not even full cigarettes. Basically what I'm getting at, I'm very paranoid, and even though everytime we go to the doc he's doing amazing, I can't help but be saddened and ashamed. What can I do to completely stop. No vaping. I also quit all of my meds when I became pregnant, which is probably why the smoking has been the hardest to drop (welbutrin, lamictal and propranolol). I'm not looking for criticism, just advice. I want my baby to be healthy but I worry if I don't have something else to lean on, I might stress too much and miscarry anyway. Help!