I'm not really sure but I do know that it is impossible for you to have a period while pregnant so it is more likely that you had some bleeding and misinterpreted it for your regular cycle. Its no biggie, my mom did the same thing until she was 6 month along with me! In most cases things turn out normally. I smoke all through my first pregnancy and didn't quit until I was halfway along with my second pregnancy and they are fine. I don't recommend it, as it can be detrimental, but I was young and naive and going through TOO much for my age. But since you quit you really are doing the best thing for your baby. That is awesome! One thing is certain, worrying about the unknown can cause unnecessary stress not just for you, but for your baby. Think positively and try to reassure yourself every time you hear how well your baby is doing, with every kick when the time comes. Just do better NOW, you know. Maybe others could give you some more information.