This is a bit of a tricky question. Partially, the answer depends on how long you've been drinking and how much you typically drink (and how frequently).
Assuming you're a bit of a hard drinker, though, I'll be honest with you: it takes a good year to feel really straight and normal again. And don't think that once you do, you can start drinking again. Because if you do, and trust me, or go find out yourself, you'll be right back to your old self in about a week! All that hard work for nothing!
I know a lot of people don't want to hear that it takes a year to be normal. But consider the fact that most hard drinkers have already been drinking many years, changing, as it were, the chemistry in their very brains--the very brains that try to develop under the stress of booze and/or other drugs--and that large aspects of our personality has been coded, if you will, through the filter of drugs and alcohol, so much so that normal ceases to exist in a sober context. Which is why I think, at least, that it takes a year to sort of stand on your own two feet again and look around and ask yourself what you'd actually like to do with your life instead of just fuck off all the time, and/or hurt those close to you, damage your own capabilities, not act on potential, and generally just become a full on low-life.
Yes, I think it takes a year. By the way, I've been sober a year and almost 8 months.
And therapy of some sort might be in order. Many drinkers have to really get used to the idea that they are not the center of all existence, and that their needs, however pressing previously, have actually been quite banal, animistic, and immature.
Anyway, for about 2 months you will be exhausted. Don't fight it. Just try to find a place of comfort to exist from within the sea of exhaustion. Slowly, it will fade. Try to do things slowly and in small increments. I can't stress that enough. The good things in life, like learning a language, cannot simply "be" accomplished in a day or two. They take a lot of time (okay, if you are between 4 and 6 years old, language acquisition is not the best example, but I'll assume nobody is of that age anymore).
So, take a deep breath. Take a walk. Make a cup of tea. Watch your habits. You will have anxiety upticks, of which smoking and coffee and sugar might seem ameliorative or anodyne, but in fact, they contribute to these pangs of death, and I'd say cut them out for a while if possible. Bottom line is that you can learn to manage anxiety without crutches, but the transition to sober will produce discomfort in the short and medium term. About 8 months in, you'll start to feel better. A lot better. If you weren't a very hard drinker, this will happen in a month or two. Anyway, good luck to everyone. I certainly don't have all the answers, and have learned that my intuition isn't always my friend.