Drinking alcohol is fine.. When you're not pregnant. If you do become pregnant, I would could back on the alcohol a lot. I have heard it's fine to drink a glass of red wine a day. But with beer and hard liquor, they use yeasts to ferment the alcohol to be able to get it on stores shelves faster instead of letting it ferment the natural way (by letting it age), and that can harm the baby (the yeasts). This is what my doctor had told me at least.
I personally wouldn't drink at all with being pregnant, but then again, I don't drink now as it is. You make your baby more at risk for getting fetal alcohol syndrome. Here is a link for more info on that:
http://www.Nofas.Org/ . I'd just talk to your doctor about this. S/he would be able to tell you more about it all, and be more exact.
Is your boyfriend ok if you get pregnant? I know you said you are, and hopefully he is too since he hasn't been using protection either.. If neither of you are truly ready to have a baby (unless you're trying to conceive).. I'd start wearing protection and get on some kind of birth control. If you haven't talked to your bf about things.. I'd talk to him now since you could be pregnant with having unprotected sex so much lately. How old are you both if I may ask?