I'd be a hypocrite if I judged you. What you did certainly happens to some of us occasionally.

I used to be a heavy drinker before I accepted medications. My average was 8-12 drinks per night, with barely a real hangover. In fact, when I was hospitalized the first time they were even calling me an alcoholic, though in my particular case that proved to be untrue. I was very unstable for a long time and sometimes "slipped", but over time (and depending on the medication I was taking), even small amounts of alcohol had terrible physical effects on me, including blackouts (if I drank even as little as 4 or 5 drinks in a sitting). Even later I'd get upset stomachs and general malaise with even 1 drink consumed too quickly. It's really not worth it anymore. I don't get the real pleasure I used to get from it.

I do occasionally go to a bar and have a (1) beer. I guess I go enough that they occasionally offer me a second drink on the house, but I have to refuse it. Instead I've asked for a dessert as a replacement. Or the bartender I usually sees knows enough now that they just give me my one and only drink for free on those special occasions. The drinks at that pub you went to are comparitively small. That's good. Most all drinks in my local bars are "pints", which are really more like 12 oz. Some bars do offer "small" drinks that are maybe 8-10 oz. I usually get them. Do try to stick with just one from now on, if possible. After that beer, why don't you treat yourself to a dessert or coffee if you want to stay longer to chat up the person next to you.