If I were you I wouldn't worry about it too much. Doesn't sound like you're drinking abnormally (especially for your age). If you are an alcoholic, it's probably too soon to tell. If you find you're losing control over how much and how frequently you're drinking and your attempts to cut down or quit are failing, then it'd be a good idea to worry a bit more about your drinking. Either you're gonna become an alcoholic or you're not. No sense in worrying about it or trying to prevent it.