I dont smoke so I'm not sure about that (my sis did smoke her whole pregnancy- she found out around 2 1/2 months and the DR told her it would be harder on the baby stress wise if she was to quit) I have given up alcohol-I drank the night before I o'd last time and M/c so I dont want to take any chances. I do frequent the Non-alcoholic drinks when I miss it. Spring break is coming up and I will be going NON alcoholic unless AF shows her ugly head.
If you drank or smoked before you knew don't stress yourself but I would stay away now that you know.
Alcohol consumption before you become pregnant doesn't affect the baby. Unless you have some kind of chronic alcohol disease, like scirrosis of the liver, I can't imagine it would affect a future pregnancy, if you don't drink while you're pregnant.
Smoking is a little different. There are studies that show if you quit smoking immediately prior to getting pregnant, or during your pregnancy, your baby will still suffer from low birth weight, which is what babies of smokers suffer from.
If you quit both habits early before getting pregnant, it doesn't seem like you have any worries.