I think if you are trying to have a child you should abstain from these activities, they're both known to cause problems. And while some people drink and smoke when they have no idea they're pregnant and their children turn out fine doesn't mean you should knowingly subject your child to them. The fact that you're asking means you think you shouldn't be doing it, and that gut feeling is right.
...they could both also cause a miscarriage for sure.
Technically, drinking SLOWLY won't harm your baby, but smoking definitely will. Read "Expecting Better" for more info.
Most likely the egg and sperm haven't implanted yet. I asked my dr about the same issue with having a few drinks before I had even realized I was pregnant (I found out I was pregnant a month after conceiving) She said not to worry because the fetus hadn't implanted itself yet. As long as you've realized your pregnant obviously and stopped these things I'm sure everything will be fine.