There are a number of alcoholism symptoms to watch out for, but it depends a bit on whether you are diagnosing yourself or somebody else. There are special points about each situation.
First of all, if you are trying to diagnose someone else, you are probably wasting your time. When it comes to diagnosing addiction, it really does not matter in terms of actionable recovery unless the person themselves admits to their problem and fully accepts it.
Seriously, imagine that your friend Dan is drinking every single day and falling asleep in a pile of vomit. You don’t diagnose him one day by reading on the internet and then suddenly exclaim to him “Oh my gosh, Dan! Today I figured out that you are an alcoholic! Now we know what the big problem is!” This is not typical and it obviously won’t change anything. More likely is that the problems have been building for a long time, and Dan fully admits that he drinks way to much. The question is: does Dan accept that he cannot drink successfully? Admitting the problem versus accepting the condition. Two different things.
Bottom line is: diagnosing someone else with alcoholism or addiction is useless. They must come to their own conclusion, and then take it a step further to get real help. Denial is so powerful that having someone else tell them they are addicted is completely irrelevant. It means nothing. They must learn it from themselves.
Now if you are attempting to diagnose your own alcoholism, then you only need to watch for honest you can be with your drinking and the way that you react to your drinking. The only tricky thing here is that there are 2 flavors of alcoholic: the straight up drunk and the binge drinker. If you are a binge drinker then you might have more trouble diagnosing yourself, because a binge drinker can go for long periods of time without drinking anything. But, if you only get into trouble after you have been drinking, then periods of sobriety do not matter much. Your drinking is a problem and you always return to it, even in spite of heavy consequences.
Symptoms of alcoholism go beyond the amount that we drink or how often we drink. The real symptom is the way in which we have a tendency to self medicate. If you escape from problems or medicate your fear with chemicals, then that is a huge indicator right there.