Whenever someone asks this question I always tell them "people who aren't addicted don't question whether they are addicted". If your drinking is so excessive and causing enough problems for you to wonder if you are an alcoholic then the answer is most likely yes.
The big test would be to tell yourself you aren't going to drink for a month and if you find that it is extremely hard and your cravings are very strong then there is your answer. People who aren't addicted don't think about drinking all the time, they don't have anxiety or cravings when they don't drink, they don't get moody, etc.