A person with obsessive-compulsive disorder (OCD) may have obsessive thoughts, compulsive behavior, or both.
Symptoms of obsessions include:
Having involuntary and persistent thoughts that appear to be senseless (such as an overwhelming fear of dirt or persistent worry about a past event) and cause anxiety or distress
Knowing that these thoughts come from one's own imagination, not from outside factors (except in children) but still unable to control the thoughts
Symptoms of compulsions...