There are functional measures of addiction problems. These concern the effects your use has on your life, or the consequences. Consider the following questions:

How often do you find that you drink or use more than you intended?
How often do you do things whilst intoxicated that you regret later?
How often do others in your life complain to you about the amount you are drinking or using?
How often has your work suffered due to drug use?
How often do you drink or use because it's the only way to have a good time?
How often do you become defensive or secretive when anyone asks about your drinking or using?
How often do you block out disturbing thoughts about your life with drinking or using?
How often do you find yourself anticipating when you will drink or use again?
How often do you try to hide how much you've been drinking or using?
How often are you unable to refuse drugs or a drink when they are offered to you?
How often have you tried to cut down and failed?

If you recognized yourself in some of these situations don't worry - that need not mean you have an addiction. If ALL the situations applied to you then yes, you probably do have a problem.