Some key factors in determining if you are an alcoholic are:
1) Can you stop drinking alcohol before you are completely wasted? Do you keep drinking alcohol until it is all gone? In other words, do you have voluntary control over your alcohol consumption? If you do control how much you drink, that is a huge point in favor of not being alcoholic.
2) Is the amount of alcohol you drink having a negative effect on your life? Are you missing work or school due to hang-overs? Do you plan your activities around drinking opportunities? Are you being isolated from your family by being drunk or hung-over? In other words, is drinking alcohol becoming the most important thing in your life?
3) Do you drink alcohol at inappropriate times? Are you drinking while alone with your young children? Drinking and driving? Drinking at work? This shows an increasing disregard for your own safety, and that of others.
If any of these factors are present, then you are strongly at risk of a problem. If two factors are present then you do have a problem.
In my experience as a counselor, people with the self-awareness to ask such questions as you are asking rarely get into deep trouble, since they can see where they are going. Most alcoholics have an extraordinary capacity for self-delusion and denial and therefore never figure out what is happening to them until things are far out of control.
If you really want to know if you are an alcoholic, or at risk, you might ask those around you what their impression is. But since you are concerned about your own behavior, and since you admit to being a little out of control with the drinking, i.e. saying that you don't want to have a beer but having one anyway, that would be enough for me to say to chill out on the alcohol for some time and figure out what is going on and what role you want alcohol to play in your life.
Take care.