If the answer is yes, then don't wait, talk to a psychologist soon. Reactive depression is called an Adjustment Disorder with depressed mood. This means that something traumatic occurred in your life, such as a relationship breakup, or loss of a job, and you became mildly to moderately depressed as a result. Psychological treatment can definitely help you to feel better, and will help you get your life back on track sooner, rather than later, but you can still manage okay. If a life crisis occurs and you develop symptoms of a major depression, then it is a major depression, even if it is also a reactive depression.
Dysthymic disorder is a chronic, low level depression, that continues for years.
Occasionally, individuals with dysthymia also experience a major depression, when a life crisis occurs. If you are depressed all the time, even if only mildly depressed, you should consult with a psychologist. You don't have to live your life in depression. In such a case, the treatment will probably take longer, because of the chronic depression underneath the major depression. Depression, not otherwise specified, is a category used by psychologists when the symptoms do not fit neatly into one of the other categories.